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  Subjects -> CHEMISTRY (Total: 842 journals)
    - ANALYTICAL CHEMISTRY (50 journals)
    - CHEMISTRY (594 journals)
    - CRYSTALLOGRAPHY (21 journals)
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    - INORGANIC CHEMISTRY (41 journals)
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CHEMISTRY (594 journals)                  1 2 3 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 8)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Full-text available via subscription   (Followers: 33)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 17)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 23)
ACS Macro Letters     Full-text available via subscription   (Followers: 23)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 39)
ACS Nano     Full-text available via subscription   (Followers: 228)
ACS Photonics     Full-text available via subscription   (Followers: 11)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 21)
Acta Chemica Iasi     Open Access   (Followers: 2)
Acta Chimica Sinica     Full-text available via subscription   (Followers: 1)
Acta Chimica Slovaca     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Scientifica Naturalis     Open Access   (Followers: 2)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 5)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 7)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 5)
Advanced Functional Materials     Hybrid Journal   (Followers: 50)
Advanced Science Focus     Free   (Followers: 3)
Advances in Chemical Engineering and Science     Open Access   (Followers: 53)
Advances in Chemical Science     Open Access   (Followers: 13)
Advances in Chemistry     Open Access   (Followers: 14)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 18)
Advances in Drug Research     Full-text available via subscription   (Followers: 22)
Advances in Enzyme Research     Open Access   (Followers: 9)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 15)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 19)
Advances in Nanoparticles     Open Access   (Followers: 14)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15)
Advances in Polymer Science     Hybrid Journal   (Followers: 41)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 19)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Science and Technology     Full-text available via subscription   (Followers: 12)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 2)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 3)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 67)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 14)
American Journal of Chemistry     Open Access   (Followers: 26)
American Journal of Plant Physiology     Open Access   (Followers: 13)
American Mineralogist     Hybrid Journal   (Followers: 14)
Analyst     Full-text available via subscription   (Followers: 38)
Angewandte Chemie     Hybrid Journal   (Followers: 159)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 211)
Annales UMCS, Chemia     Open Access   (Followers: 1)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 1)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 3)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 8)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 13)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 14)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Hybrid Journal  
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7)
Applied Spectroscopy     Full-text available via subscription   (Followers: 23)
Applied Surface Science     Hybrid Journal   (Followers: 28)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 2)
Asian Journal of Biochemistry     Open Access   (Followers: 1)
Atomization and Sprays     Full-text available via subscription   (Followers: 3)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access   (Followers: 1)
Biochemical Pharmacology     Hybrid Journal   (Followers: 10)
Biochemistry     Full-text available via subscription   (Followers: 287)
Biochemistry Insights     Open Access   (Followers: 5)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 9)
Bioinspired Materials     Open Access   (Followers: 5)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 1)
Biomacromolecules     Full-text available via subscription   (Followers: 19)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 6)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 4)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 109)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 94)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 2)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 1)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 2)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 3)
Cakra Kimia (Indonesian E-Journal of Applied Chemistry)     Open Access  
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Hybrid Journal   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 3)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 66)
Catalysis for Sustainable Energy     Open Access   (Followers: 6)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 8)
Catalysis Science and Technology     Free   (Followers: 6)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 7)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 12)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 70)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 23)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 19)
Chemical Reviews     Full-text available via subscription   (Followers: 174)
Chemical Science     Open Access   (Followers: 21)
Chemical Technology     Open Access   (Followers: 16)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemical Week     Full-text available via subscription   (Followers: 8)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 55)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 25)
ChemInform     Hybrid Journal   (Followers: 8)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 6)
Chemistry & Biology     Full-text available via subscription   (Followers: 30)
Chemistry & Industry     Hybrid Journal   (Followers: 5)
Chemistry - A European Journal     Hybrid Journal   (Followers: 142)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 15)
Chemistry and Materials Research     Open Access   (Followers: 18)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry International     Hybrid Journal   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 45)
Chemistry of Materials     Full-text available via subscription   (Followers: 261)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry World     Full-text available via subscription   (Followers: 22)
Chemistry-Didactics-Ecology-Metrology     Open Access  
ChemistryOpen     Open Access   (Followers: 2)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 2)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 15)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 9)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 10)
Chromatographia     Hybrid Journal   (Followers: 24)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Cogent Chemistry     Open Access  
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 10)
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 8)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 3)
Combustion Science and Technology     Hybrid Journal   (Followers: 18)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Composite Interfaces     Hybrid Journal   (Followers: 6)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 2)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 9)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 2)
Copernican Letters     Open Access  
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 5)
Crystal Structure Theory and Applications     Open Access   (Followers: 3)
CrystEngComm     Full-text available via subscription   (Followers: 11)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 58)
Dalton Transactions     Full-text available via subscription   (Followers: 21)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 12)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  
Drying Technology: An International Journal     Hybrid Journal   (Followers: 4)
Eclética Química     Open Access   (Followers: 1)
Ecological Chemistry and Engineering S     Open Access   (Followers: 4)
Ecotoxicology and Environmental Contamination     Open Access  
Educación Química     Open Access   (Followers: 1)
Education for Chemical Engineers     Hybrid Journal   (Followers: 5)
EJNMMI Radiopharmacy and Chemistry     Open Access  
Elements     Full-text available via subscription   (Followers: 2)
Environmental Chemistry     Hybrid Journal   (Followers: 9)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 4)
Environmental Science & Technology Letters     Full-text available via subscription   (Followers: 5)
Environmental Science : Nano     Partially Free   (Followers: 1)

        1 2 3 | Last

Journal Cover Advanced Functional Materials
  [SJR: 5.21]   [H-I: 203]   [50 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1616-301X - ISSN (Online) 1616-3028
   Published by John Wiley and Sons Homepage  [1577 journals]
  • Cancer Cell Membrane-Biomimetic Oxygen Nanocarrier for Breaking
           Hypoxia-Induced Chemoresistance
    • Authors: Hao Tian; Zhenyu Luo, Lanlan Liu, Mingbin Zheng, Ze Chen, Aiqing Ma, Ruijing Liang, Zhiqun Han, Chengyu Lu, Lintao Cai
      Abstract: The inadequate oxygen supply in solid tumor causes hypoxia, which leads to drug resistance and poor chemotherapy outcomes. To solve this problem, a cancer cell membrane camouflaged nanocarrier is developed with a polymeric core encapsulating hemoglobin (Hb) and doxorubicin (DOX) for efficient chemotherapy. The designed nanoparticles (DHCNPs) retain the cancer cell adhesion molecules on the surface of nanoparticles for homologous targeting and possess the oxygen-carrying capacity of Hb for O2-interfered chemotherapy. The results show that DHCNPs not only achieve higher tumor specificity and lower toxicity by homologous targeting but also significantly reduce the exocytosis of DOX via suppressing the expressions of hypoxia-inducible factor-1α, multidrug resistance gene 1, and P-glycoprotein, thus resulting in safe and high-efficient chemotherapy. This work presents a new paradigm for targeted oxygen interference therapy by conquering hypoxia-involved therapeutic resistance and achieves effective treatment of solid tumors.The biomimetic oxygen nanocarrier (DHCNPs), consisting of a doxorubicin (DOX)/Hb-loaded polymeric core and cancer cell membrane shell, exhibits highly effective delivery of drug and oxygen to homologous cancer cells. Sufficient oxygen supply alters tumor hypoxia and consequently downregulates the expressions of hypoxia-inducible factor-1α, multidrug resistance gene 1, and P-glycoprotein, resulting in inhibited DOX efflux and enhanced chemotherapy with intense intracellular DOX accumulation.
      PubDate: 2017-08-18T06:17:33.204799-05:
      DOI: 10.1002/adfm.201703197
       
  • Tissue-Engineered Peripheral Nerve Interfaces
    • Authors: Benjamin S. Spearman; Vidhi H. Desai, Sahba Mobini, Matthew D. McDermott, James B. Graham, Kevin J. Otto, Jack W. Judy, Christine E. Schmidt
      Abstract: Research on neural interfaces has historically concentrated on development of systems for the brain; however, there is increasing interest in peripheral nerve interfaces (PNIs) that could provide benefit when peripheral nerve function is compromised, such as for amputees. Efforts focus on designing scalable and high-performance sensory and motor peripheral nervous system interfaces. Current PNIs face several design challenges such as undersampling of signals from the thousands of axons, nerve-fiber selectivity, and device–tissue integration. To improve PNIs, several researchers have turned to tissue engineering. Peripheral nerve tissue engineering has focused on designing regeneration scaffolds that mimic normal nerve extracellular matrix composition, provide advanced microarchitecture to stimulate cell migration, and have mechanical properties like the native nerve. By combining PNIs with tissue engineering, the goal is to promote natural axon regeneration into the devices to facilitate close contact with electrodes; in contrast, traditional PNIs rely on insertion or placement of electrodes into or around existing nerves, or do not utilize materials to actively facilitate axon regeneration. This review presents the state-of-the-art of PNIs and nerve tissue engineering, highlights recent approaches to combine neural-interface technology and tissue engineering, and addresses the remaining challenges with foreign-body response.Peripheral nerve interfaces (PNIs) as part of advanced prosthetic devices allow for communication between the device and nerves by providing motor control and sensory feedback. To improve PNIs, researchers have turned to tissue engineering. This review presents the state-of-the-art of PNIs and nerve tissue engineering, highlights recent approaches to combine neural-interface technology and tissue engineering, and addresses the remaining challenges.
      PubDate: 2017-08-18T06:16:54.571203-05:
      DOI: 10.1002/adfm.201701713
       
  • Using First-Principles Calculations for the Advancement of Materials for
           Rechargeable Batteries
    • Authors: Gabin Yoon; Do-Hoon Kim, Inchul Park, Donghee Chang, Byunghoon Kim, Byungju Lee, Kyungbae Oh, Kisuk Kang
      Abstract: Rechargeable batteries have been regarded as leading candidates for energy storage systems to satisfy soaring energy demands and ensure efficient energy use, and intensive efforts have thus been focused on enhancing their energy densities and power capabilities. First-principles calculations based on quantum mechanics have played an important role in obtaining a fundamental understanding of battery materials, thus providing insights for material design. In this feature article, the theoretical approaches used to determine key battery properties, such as the voltage, phase stability, and ion-diffusion kinetics, are reviewed. Moreover, the recent contribution of first-principles calculations to the interpretation of complicated experimental characterization measurements on battery materials, such as those obtained using X-ray absorption spectroscopy, electron energy-loss spectroscopy, nuclear magnetic resonance spectroscopy, and transmission electron microscopy, are introduced. Finally, perspectives are provided on the research direction of first-principles calculations for the development of advanced batteries, including the further development of theories that can accurately describe the dissolved species, amorphous phases, and surface reactions that are integral to the operation of future battery systems beyond Li-ion batteries.Theoretical approaches used to determine key battery properties such as the voltage, phase stability, and ion-diffusion kinetics are reviewed. Moreover, the recent contribution of first-principles calculations to the interpretation of complicated experimental characterization measurements on battery materials is introduced, and provides perspectives on the research direction of first-principles calculations for the development of advanced batteries.
      PubDate: 2017-08-18T06:16:07.491316-05:
      DOI: 10.1002/adfm.201702887
       
  • Plasmonic Dual-Enhancement and Precise Color Tuning of Gold Nanorod@SiO2
           Coupled Core–Shell–Shell Upconversion Nanocrystals
    • Authors: Fengwen Kang; Jijun He, Tianying Sun, Zhi Yong Bao, Feng Wang, Dang Yuan Lei
      Abstract: The last decade has witnessed the remarkable research progress of lanthanide-doped upconversion nanocrystals (UCNCs) at the forefront of promising applications. However, the future development and application of UCNCs are constrained greatly by their underlying shortcomings such as significant nonradiative processes, low quantum efficiency, and single emission colors. Here a hybrid plasmonic upconversion nanostructure consisting of a GNR@SiO2 coupled with NaGdF4:Yb3+,Nd3+@NaGdF4:Yb3+,Er3+@NaGdF4 core–shell–shell UCNCs is rationally designed and fabricated, which exhibits strongly enhanced UC fluorescence (up to 20 folds) and flexibly tunable UC colors. The experimental findings show that controlling the SiO2 spacer thickness enables readily manipulating the intensity ratio of the Er3+ red, green, and blue emissions, thereby allowing us to achieve the emission color tuning from pale yellow to green upon excitation at 808 nm. Electrodynamic simulations reveal that the tunable UC colors are due to the interplay of plasmon-mediated simultaneous excitation and emission enhancements in the Er3+ green emission yet only excitation enhancement in the blue and red emissions. The results not only provide an upfront experimental design for constructing hybrid plasmonic UC nanostructures with high efficiency and color tunability, but also deepen the understanding of the interaction mechanism between the Er3+ emissions and plasmon resonances in such complex hybrid nanostructure.The plasmon-mediated selective excitation and emission enhancement on the blue, green, and red emissions of Er3+ in a rationally designed hybrid plasmonic upconversion (UC) nanostructure enables achieving enhanced UC luminescence and tunable UC color.
      PubDate: 2017-08-17T02:04:19.129712-05:
      DOI: 10.1002/adfm.201701842
       
  • Self-Assembled Hydrogel Fiber Bundles from Oppositely Charged
           Polyelectrolytes Mimic Micro-/Nanoscale Hierarchy of Collagen
    • Authors: Shilpa Sant; Daniela F. Coutinho, Akhilesh K. Gaharwar, Nuno M. Neves, Rui L. Reis, Manuela E. Gomes, Ali Khademhosseini
      Abstract: Fiber bundles are present in many tissues throughout the body. In most cases, collagen subunits spontaneously self-assemble into a fibrilar structure that provides ductility to bone and constitutes the basis of muscle contraction. Translating these natural architectural features into a biomimetic scaffold still remains a great challenge. Here, a simple strategy is proposed to engineer biomimetic fiber bundles that replicate the self-assembly and hierarchy of natural collagen fibers. The electrostatic interaction of methacrylated gellan gum with a countercharged chitosan polymer leads to the complexation of the polyelectrolytes. When directed through a polydimethylsiloxane channel, the polyelectrolytes form a hierarchical fibrous hydrogel demonstrating nanoscale periodic light/dark bands similar to D-periodic bands in native collagen and align parallel fibrils at microscale. Importantly, collagen-mimicking hydrogel fibers exhibit robust mechanical properties (MPa scale) at a single fiber bundle level and enable encapsulation of cells inside the fibers under cell-friendly mild conditions. Presence of carboxyl- (in gellan gum) or amino- (in chitosan) functionalities further enables controlled peptide functionalization such as Arginylglycylaspartic acid (RGD) for biochemical mimicry (cell adhesion sites) of native collagen. This biomimetic-aligned fibrous hydrogel system can potentially be used as a scaffold for tissue engineering as well as a drug/gene delivery vehicle.Bottom-up self-assembly of oppositely charged polysaccharides in a microfluidic channel to form hydrogel fiber bundles is reported. These fiber bundles exhibit micro- to nanoscale hierarchy forming fibers, fibrils to light and dark banding pattern similar to that observed in native collagen. Polysaccharides allow easy peptide functionalization such as RGD to recapitulate integrin binding sites in collagen and promote cell adhesion.
      PubDate: 2017-08-16T13:17:04.384207-05:
      DOI: 10.1002/adfm.201606273
       
  • Drug Delivery: Plant-Based Hollow Microcapsules for Oral Delivery
           Applications: Toward Optimized Loading and Controlled Release (Adv. Funct.
           Mater. 31/2017)
    • Authors: Michael G. Potroz; Raghavendra C. Mundargi, Jurriaan J. Gillissen, Ee-Lin Tan, Sigalit Meker, Jae H. Park, Haram Jung, Soohyun Park, Daeho Cho, Sa-Ik Bang, Nam-Joon Cho
      Abstract: In article number 1700270, Sa-Ik Bang, Nam-Joon Cho, and co-workers describe how to optimize loading and controlled release of plant-based hollow microcapsules for oral drug delivery. Extracted sporopollenin exine capsules from sun flowers are successfully loaded with protein and formulated into enterically coated tablets.
      PubDate: 2017-08-16T07:39:14.456719-05:
      DOI: 10.1002/adfm.201770184
       
  • Drug Delivery: Multifunctional Molecular Beacon Micelles for Intracellular
           mRNA Imaging and Synergistic Therapy in Multidrug-Resistant Cancer Cells
           (Adv. Funct. Mater. 31/2017)
    • Authors: Ruili Zhang; Shi Gao, Zhongliang Wang, Da Han, Lin Liu, Qingjie Ma, Weihong Tan, Jie Tian, Xiaoyuan Chen
      Abstract: An anti-MDR1 molecular-beacon-based micelle nanosystem is demonstrated by Zhongliang Wang, Qingjie Ma, Xiaoyuan Chen, and co-workers in article number 1701027. Owing to its ingenious design, the nanosystem is able to successfully administer both a MDR1 gene silencer and a chemotherapeutic agent in a sequential way to produce a synergistic therapeutic effect, enhancing chemotherapeutic efficacy to OVCAR8/ADR cells significantly.
      PubDate: 2017-08-16T07:39:13.998733-05:
      DOI: 10.1002/adfm.201770179
       
  • Contents: (Adv. Funct. Mater. 31/2017)
    • PubDate: 2017-08-16T07:39:13.525873-05:
      DOI: 10.1002/adfm.201770182
       
  • Organic Light-Emitting Diodes: White Organic LED with a Luminous Efficacy
           Exceeding 100 lm W−1 without Light Out-Coupling Enhancement Techniques
           (Adv. Funct. Mater. 31/2017)
    • Authors: Sheng-Fan Wu; Si-Hua Li, Ya-Kun Wang, Chen-Chao Huang, Qi Sun, Jiao-Jiao Liang, Liang-Sheng Liao, Man-Keung Fung
      Abstract: Man-Keung Fung, and co-workers discuss a white organic light-emitting diode (OLED) based on a newly designed blue thermally activated delayed fluorescent (TADF) exciplex host. Using the exciplex as the host for two-color based phosphorescent white OLEDs provides super-high luminous efficacy and external quantum efficiency. This work provides a promising avenue to boost the development of low power-consumption applications in display and lighting market.
      PubDate: 2017-08-16T07:39:10.019713-05:
      DOI: 10.1002/adfm.201770180
       
  • Masthead: (Adv. Funct. Mater. 31/2017)
    • PubDate: 2017-08-16T07:39:09.615259-05:
      DOI: 10.1002/adfm.201770181
       
  • Shape Anisotropy: Anisotropy in Shape and Ligand-Conjugation of Hybrid
           Nanoparticulates Manipulates the Mode of Bio–Nano Interaction and Its
           Outcome (Adv. Funct. Mater. 31/2017)
    • Authors: Xiaoyou Wang; Li Lin, Renfa Liu, Min Chen, Binlong Chen, Bo He, Bing He, Xiaolong Liang, Wenbing Dai, Hua Zhang, Xueqing Wang, Yiguang Wang, Zhifei Dai, Qiang Zhang
      Abstract: Anisotropic modification on nanodiscs could trigger huge differences in their endocytosis mode and following behaviors. In article number 1700406 Zhifei Dai, Qiang Zhang, and co-workers design analyze the cellular uptake of nanoparticulates differing in anisotropy of shape and ligand modification. This anisotropy-based approach is promising for manipulating the biointeraction mode of nanomaterials and its outcome.
      PubDate: 2017-08-16T07:39:08.675095-05:
      DOI: 10.1002/adfm.201770183
       
  • Colorimetric Nanofibers as Optical Sensors
    • Authors: Ella Schoolaert; Richard Hoogenboom, Karen De Clerck
      Abstract: Sensors play a major role in many applications today, ranging from biomedicine to safety equipment, where they detect and warn us about changes in the environment. Nanofibers, characterized by high porosity, flexibility, and a large specific surface area, are the ideal material for ultrasensitive, fast-responding, and user-friendly sensor design. Indeed, a large specific surface area increases the sensitivity and response time of the sensor as the contact area with the analyte is enlarged. Thanks to the flexibility of membranes, nanofibrous sensors cannot only be applied in high-end analyte detection, but also in personal, daily use. Many different nanofibrous sensors have already been designed; albeit, the most straightforward and easiest-to-interpret sensor response is a visual change in color, which is of particular interest in the case of warning signals. Recently, many researchers have focused on the design of so-called colorimetric nanofibers, which typically involve the incorporation of a colorimetric functionality into the nanofibrous matrix. Many different strategies have been used and explored for colorimetric nanofibrous sensor design, which are outlined in this feature article. The many examples and applications demonstrate the value of colorimetric nanofibers for advanced optical sensor design, and could provide directions for future research in this area.The design of colorimetric nanofibrous materials for advanced, ultrasensitive, and user-friendly optical sensors is a hot topic recently. By combining electrospinning and a chromogenic agent, color-changing nanofibers responsive to specific analytes are designed, which are applied in many application areas. This feature article gives an overview of several techniques used for the production of colorimetric nanofibrous sensors.
      PubDate: 2017-08-16T05:07:30.183493-05:
      DOI: 10.1002/adfm.201702646
       
  • Reversible Attachment with Tailored Permeability: The Feather Vane and
           Bioinspired Designs
    • Authors: Tarah N. Sullivan; Michael Chon, Rajaprakash Ramachandramoorthy, Michael R. Roenbeck, Tzu-Tying Hung, Horacio D. Espinosa, Marc A. Meyers
      Abstract: In bird flight, the majority of the wing surface consists of highly refined and hierarchically organized feathers. They are composed of barbs that stem from the feather shaft and barbules that branch from barbs, forming a rigid feather vane. Barbules provide adhesion within the vane through an interlocking hook-and-groove mechanism to allow for the effective capture of air. This functional adhesive can reattach if structures unfasten from one another, preventing catastrophic damage of the vane. Here, using pelican primary feathers as a model material, we investigate the in-plane adhesion and stiffness of barbules. With guineafowl, pelican, and dove feathers, we determine the effect of barbules on the feather vane's ability to capture air. The vane is found to have directional permeability, and the effect of detaching barbules on the feather's competency is determined to be a function of barb dimensions. Interestingly, barbule spacing is found to vary within a narrow 8–16 µm range for birds weighing from 4–11 000 g (hummingbird to condor). Additionally, bioinspired barbules are fabricated through additive manufacturing to study the complexities of the vane. Barbules are underexplored structures imperative to the adeptness of the feather in flight, with the potential to provide bioinspired aerospace materials.The flying feathers of birds are hierarchically organized structures with barbs branching from the feather shaft and interlocking barbules branching from barbs to form a rigid vane. Here, the effect of barbules on the feather vane's ability to capture air is determined, and the barbule's effectiveness in holding the vane together is investigated.
      PubDate: 2017-08-16T05:06:05.605703-05:
      DOI: 10.1002/adfm.201702954
       
  • Thermo-Phototronic Effect Enhanced InP/ZnO Nanorod Heterojunction Solar
           Cells for Self-Powered Wearable Electronics
    • Authors: Kewei Zhang; Ya Yang
      Abstract: Enhancing interfacial charge transfer by the inner electric field is crucial for improving photovoltaic performance of heterojunction solar cells. Recent studies are focusing on how to utilize piezo-phototronic effect (strain-induced inner electric field) to modulate the interfacial charge transfer, whereas the preservation of solar cells from structure damage and performance decline under long-term strain becomes increasingly challenging. Here, without use of strain, a thermo-phototronic effect is presented to enhance the interfacial charge transfer in InP/ZnO nanorod heterojunction solar cells. Under a temperature gradient of 3.5 °C across the device, the output current and voltage of the solar cell under weak light illumination are enhanced by 27.3 and 76%, respectively. Moreover, the performance enhancement can be further regulated by applying different temperature gradients. This study serves as proof-of-principle for the thermo-phototronic effect and pushes forward the maximum utilization of solar energy by a one-circuit-based photovoltaic-thermoelectric system.A one-circuit-based photovoltaic-thermoelectric system in terms of thermo-phototronic effect is designed to modulate the interfacial charge transfer for enhancing the output performance of heterojunction solar cells.
      PubDate: 2017-08-15T02:21:46.773943-05:
      DOI: 10.1002/adfm.201703331
       
  • Space-Confined Chemical Vapor Deposition Synthesis of Ultrathin HfS2
           Flakes for Optoelectronic Application
    • Authors: Chaoyi Yan; Lin Gan, Xing Zhou, Jun Guo, Wenjuan Huang, Jianwen Huang, Bao Jin, Jie Xiong, Tianyou Zhai, Yanrong Li
      Abstract: Due to the predicted excellent electronic properties superior to group VIB (Mo and W) transition metal dichalcogenides (TMDs), group IVB TMDs have enormous potential in nanoelectronics. Here, the synthesis of ultrathin HfS2 flakes via space-confined chemical vapor deposition, realized by an inner quartz tube, is demonstrated. Moreover, the effect of key growth parameters including the dimensions of confined space and deposition temperature on the growth behavior of products is systematically studied. Typical as-synthesized HfS2 is a hexagonal-like flake with a smallest thickness of ≈1.2 nm (bilayer) and an edge size of ≈5 µm. The photodetector based on as-synthesized HfS2 flakes demonstrates excellent optoelectronic performance with a fast photoresponse time (55 ms), which is attributed to the high-quality crystal structure obtained at a high deposition temperature and the ultraclean interface between HfS2 and the mica substrate. With such properties HfS2 holds great potential for optoelectronics applications.High-quality ultrathin HfS2 flakes are synthesized for the first time via an improved chemical vapor deposition method introducing a confined space, which is employed to construct a precursor growth environment that is stable and precisely tunable regarding reactant concentrations. The photodetector based on the HfS2 flake shows a fast response time of 55 ms.
      PubDate: 2017-08-15T02:20:56.440859-05:
      DOI: 10.1002/adfm.201702918
       
  • Dual Near-Infrared Two-Photon Microscopy for Deep-Tissue Dopamine
           Nanosensor Imaging
    • Authors: Jackson T. Del Bonis-O'Donnell; Ralph H. Page, Abraham G. Beyene, Eric G. Tindall, Ian R. McFarlane, Markita P. Landry
      Abstract: A key limitation for achieving deep imaging in biological structures lies in photon absorption and scattering leading to attenuation of fluorescence. In particular, neurotransmitter imaging is challenging in the biologically relevant context of the intact brain for which photons must traverse the cranium, skin, and bone. Thus, fluorescence imaging is limited to the surface cortical layers of the brain, only achievable with craniotomy. Herein, this study describes optimal excitation and emission wavelengths for through-cranium imaging, and demonstrates that near-infrared emissive nanosensors can be photoexcited using a two-photon 1560 nm excitation source. Dopamine-sensitive nanosensors can undergo two-photon excitation, and provide chirality-dependent responses selective for dopamine with fluorescent turn-on responses varying between 20% and 350%. The two-photon absorption cross-section and quantum yield of dopamine nanosensors are further calculated, and a two-photon power law relationship for the nanosensor excitation process is confirmed. Finally, the improved image quality of the nanosensors embedded 2-mm-deep into a brain-mimetic tissue phantom is shown, whereby one-photon excitation yields 42% scattering, in contrast to 4% scattering when the same object is imaged under two-photon excitation. The approach overcomes traditional limitations in deep-tissue fluorescence microscopy, and can enable neurotransmitter imaging in the biologically relevant milieu of the intact and living brain.The two-photon excitation of single-walled carbon nanotube nanosensors produces a near-infrared fluorescent signal in response to the neurotransmitter dopamine. Both the excitation (1560 nm) and emission (900–1400 nm) wavelengths fall within a local transmittance maximum for brain tissue, scalp, and cranial bone, enabling dopamine imaging deep into highly scattering media.
      PubDate: 2017-08-15T02:11:58.92909-05:0
      DOI: 10.1002/adfm.201702112
       
  • Functional Hybrid Nanopaper by Assembling Nanofibers of Cellulose and
           Sepiolite
    • Authors: M. Mar González del Campo; Margarita Darder, Pilar Aranda, Marwa Akkari, Yves Huttel, Alvaro Mayoral, Jefferson Bettini, Eduardo Ruiz-Hitzky
      Abstract: Functional heterofibrous hybrid materials are prepared in an integrative approach from aqueous dispersions of nanofibrillated cellulose and sepiolite by applying high shear homogenization and ultrasound irradiation. Both types of nanofibers remain physically cross-linked forming homogeneous and very stable high-viscosity gels that can be shaped as films and considered as “hybrid nanopapers” as well. The presence of sepiolite modifies the surface roughness of the films resulting from the casting process, which can be rendered hydrophobic, as the hydrophilic characteristics of both components resulted modulated. In addition, these fibrous hybrid systems can benefit from the properties provided by the two components, such as mechanical behavior, surface properties, and chemical reactivity. Moreover, further assembly of these hybrid nanopapers to other particulate solids, such as carbon nanotubes, magnetite, or ZnO nanoparticles, results in multifunctional hybrid nanopapers, opening a versatile way for developing other numerous organic–inorganic materials of interest in diverse applications.Herein, a functional hybrid nanopaper by assembling nanofibers of cellulose and sepiolite is demonstrated. The cross-assembly between two kinds of nanofibers of organic and inorganic nature through mechanical and sonomechanical processes results in nanostructured biohybrids showing ability toward further functionalization giving rise to functional materials with tunable properties and diverse potential applications.
      PubDate: 2017-08-15T02:08:04.430758-05:
      DOI: 10.1002/adfm.201703048
       
  • Metal–Organic Framework Derived Co3O4/TiO2/Si Heterostructured Nanorod
           Array Photoanodes for Efficient Photoelectrochemical Water Oxidation
    • Authors: Rui Tang; Shujie Zhou, Zhimin Yuan, Longwei Yin
      Abstract: A novel hierarchical structured photoanode based on metal–organic frameworks (MOFs)-derived porous Co3O4-modified TiO2 nanorod array grown on Si (MOFs-derived Co3O4/TiO2/Si) is developed as photoanode for efficiently photoelectrochemical (PEC) water oxidation. The ternary Co3O4/TiO2/Si heterojunction displays enhanced carrier separation performance and electron injection efficiency. In the ternary system, an abnormal type-II heterojunction between TiO2 and Si is introduced, because the conduction band and valence band position of Si are higher than those of TiO2, the photogenerated electrons from TiO2 will rapidly recombine with the photogenerated holes from Si, thus leading to an efficient separation of photogenerated electrons from Si/holes from TiO2 at the TiO2/Si interface, greatly improving the separation efficiency of photogenerated hole within TiO2 and enhances the photogenerated electron injection efficiency in Si. While the MOFs-derived Co3O4 obviously improves the optical-response performance and surface water oxidation kinetics due to the large specific surface area and porous channel structure. Compared with MOFs-derived Co3O4/TiO2/FTO photoanode, the synergistic function in the MOFs-derived Co3O4/TiO2/Si NR photoanode brings greatly enhanced photoconversion efficiency of 0.54% (1.04 V vs reversible hydrogen electrode) and photocurrent density of 2.71 mA cm−2 in alkaline electrolyte. This work provides promising methods for constructing high-performance PEC water splitting photoanode based on MOFs-derived materials.Metal–organic frameworks (MOF) derived Co3O4/TiO2/Si heterostructured nanorod (NR) array photoanodes for efficient photoelectrochemical water oxidation are developed. The abnormal type-II TiO2/Si heterojunction greatly improves the photogenerated hole separation and electron injection efficiencies. The synergistic function in Co3O4/TiO2/Si NR photoanode brings a greatly enhanced photoconversion efficiency of 0.54% and a photocurrent density of 2.71 mA cm−2 in an alkaline electrolyte.
      PubDate: 2017-08-15T02:07:25.223719-05:
      DOI: 10.1002/adfm.201701102
       
  • Tailored Graphitic Carbon Nitride Nanostructures: Synthesis, Modification,
           and Sensing Applications
    • Authors: Lichan Chen; Jibin Song
      Abstract: Various beneficial properties of graphitic carbon nitride (g-CN) have been discovered during the promotion of its visible-light-driven photocatalytic activity for water splitting. These properties enable g-CN working as a sensing signal transducer with multiple output modes. In this review, state-of-the-art sensing applications of tailored g-CN nanostructures in the recent years are presented. Initially, g-CN nanoarchitectures featuring large surface areas, abundance of active sites, and high dispersity in water are presented along with their preparation methods. Then, sensing applications of these g-CN nanoarchitectures are described in sequence of the immobilization of recognition elements; semiconductor and electron donating properties derive signaling transduction modes, and efficient approaches for improving sensing performances. The review is concluded with a summary and some perspectives on the challenges and future possibilities of this research field.The fabrication, sensing application, and future perspectives of graphitic carbon nitride (g-CN) based sensor are highlighted, which include the design and synthesis of g-CN nanoarchitectures that are suitable for sensor construction, the strategy of conjugation of recognition elements to g-CN nanoarchitectures, signaling transduction modes derived from g-CN's semiconductor and electron donating properties, and efficient approaches for improving sensing performances, i.e., with high sensitivity, specificity, and reproducibility.
      PubDate: 2017-08-15T02:06:46.330936-05:
      DOI: 10.1002/adfm.201702695
       
  • Nanotechnology for Neuroscience: Promising Approaches for Diagnostics,
           Therapeutics and Brain Activity Mapping
    • Authors: Anil Kumar; Aaron Tan, Joanna Wong, Jonathan Clayton Spagnoli, James Lam, Brianna Diane Blevins, Natasha G, Lewis Thorne, Keyoumars Ashkan, Jin Xie, Hong Liu
      Abstract: Unlocking the secrets of the brain is a task fraught with complexity and challenge – not least due to the intricacy of the circuits involved. With advancements in the scale and precision of scientific technologies, we are increasingly equipped to explore how these components interact to produce a vast range of outputs that constitute function and disease. Here, an insight is offered into key areas in which the marriage of neuroscience and nanotechnology has revolutionized the industry. The evolution of ever more sophisticated nanomaterials culminates in network-operant functionalized agents. In turn, these materials contribute to novel diagnostic and therapeutic strategies, including drug delivery, neuroprotection, neural regeneration, neuroimaging and neurosurgery. Further, the entrance of nanotechnology into future research arenas including optogenetics, molecular/ion sensing and monitoring, and piezoelectric effects is discussed. Finally, considerations in nanoneurotoxicity, the main barrier to clinical translation, are reviewed, and direction for future perspectives is provided.Nanoneuroscience is a promising approach to unlocking the secrets of the brain and addressing its complexities and challenges. This begins with the evolution and refinement of ever more sophisticated nanomaterials, culminating in network-operant functionalized agents.
      PubDate: 2017-08-14T01:24:18.585946-05:
      DOI: 10.1002/adfm.201700489
       
  • A Benchmark Quantum Yield for Water Photoreduction on Amorphous Carbon
           Nitride
    • Authors: Mohammad Z. Rahman; Patrick C. Tapping, Tak W. Kee, Ronald Smernik, Nigel Spooner, Jillian Moffatt, Youhong Tang, Kenneth Davey, Shi-Zhang Qiao
      Abstract: Amorphous carbon nitride (a-CN) is a less-explored but promising photocatalyst for hydrogen production. Despite an extended visible light absorption (EVLA) its low quantum efficiency (QE) for water photoreduction is a long standing problem. This implies that EVLA is not proportionally translated into collection of large amounts of photogenerated electrons. Minimizing the mismatch between light-absorption and charge-collection remains a scientific challenge. Here a sponge-like hierarchical structure of a-CN that addresses this apparent mismatch is reported. Combined experimental and finite difference time domain simulations demonstrate the ability of the a-CN sponge to induce scattering for total internal light reflection that promotes localized charge carrier generation. Diffused reflectance and transient fluorescence decay studies show good agreement with simulations with a 40% enhanced light-trapping and an ≈23 times longer electron lifetime in spongy a-CN compared with that of the bulk material. The result is a new high benchmark for hydrogen production of 203.5 µmol h−1 with a QE of 6.1% at 420 nm in a reaction system of 10 vol% triethanolamine and 1 wt% Pt cocatalyst. The enhanced water photoreduction is a result of amenable photophysical and electrochemical attributes existing within the a-CN sponge.Spongy amorphous carbon nitride (a-CN) has been developed and demonstrated for photocatalytic hydrogen production via water-splitting. Hydrogen production with a-CN has an apparent quantum efficiency of 6.1% under visible light irradiation (420 nm). This is a high benchmark for hydrogen production, superseding all previously reported a-CN photocatalysts.
      PubDate: 2017-08-14T01:22:40.525432-05:
      DOI: 10.1002/adfm.201702384
       
  • In Vivo Subcutaneous Thermal Video Recording by Supersensitive Infrared
           Nanothermometers
    • Authors: Erving C. Ximendes; Uéslen Rocha, Tasso O. Sales, Núria Fernández, Francisco Sanz-Rodríguez, Inocencio R. Martín, Carlos Jacinto, Daniel Jaque
      Abstract: Some of the old and unrealizable dreams of biomedicine have become possible thanks to the appearance of novel advanced materials such as luminescent nanothermometers, nanoparticles capable of providing a contactless thermal reading through their light emission properties. Luminescent nanothermometers have already been demonstrated to be capable of in vivo subcutaneous punctual thermal reading but their real application as diagnosis tools still requires demonstrating their actual capacity for the acquisition of in vivo, time-resolved subcutaneous thermal images. The transfer from 1D to 2D subcutaneous thermal sensing is blocked in the last years mainly due to the lack of high sensitivity luminescent nanothermometers operating in the infrared biological windows. This work demonstrates how core/shell engineering, in combination with selective rare earth doping, can be used to develop supersensitive infrared luminescent nanothermometers. Erbium, thulium, and ytterbium core–shell LaF3 nanoparticles, operating within the biological windows, provide thermal sensitivities as large as 5% °C−1. This “record” sensitivity has allowed for the final acquisition of subcutaneous thermal videos of a living animal. Subsequent analysis of thermal videos allows for an unequivocal determination of intrinsic properties of subcutaneous tissues, opening the venue to the development of novel thermal imaging-based diagnosis tools.The Er-Yb@Yb-Tm NPs are introduced as highly sensitive nanothermometers operating in the second and third biological windows. Their superior thermal sensitivity makes possible the acquisition of in vivo subcutaneous thermal videos at the small animal level. The results here presented may lead to a new era of biomedicine founded on thermal imaging based diagnosis.
      PubDate: 2017-08-14T01:22:01.090798-05:
      DOI: 10.1002/adfm.201702249
       
  • Engineering Highly Ordered Iron Titanate Nanotube Array Photoanodes for
           Enhanced Solar Water Splitting Activity
    • Authors: Hemin Zhang; Ju Hun Kim, Jin Hyun Kim, Jae Sung Lee
      Abstract: Highly ordered iron titanate (Fe2TiO5) nanotube array photoanode is synthesized on F:SnO2 glass with ultrathin anodized aluminum oxide as a hard template. Highly crystalline, yet the nanotube array morphology-preserved Fe2TiO5 is fabricated by hybrid microwave annealing (HMA). The effects of the synthesis parameters on photoelectrochemical (PEC) water splitting activity under simulated sunlight are systematically studied including HMA time, pore size, wall thickness, and length of the nanotubes to optimize the nanotube array photoanode. In addition, triple modification strategies of TiO2 underlayer, hydrogen treatment, and FeNiOx cocatalyst loading effectively improve the PEC activity further. The systematically engineered nanotube array photoanode achieves a photocurrent density of 0.93 mA cm−2 at 1.23 VRHE under 1 sun (100 mW cm−2) irradiation, which corresponds to 2.6 times that of the previous best Fe2TiO5 photoanode. In addition, the photocurrent onset potential shifts cathodically by ≈280 mV relative to the pristine nanotube array electrode.A highly ordered Fe2TiO5 nanotube array photoanode with high crystallinity is synthesized with ultrathin anodic aluminum oxide as a template and hybrid microwave annealing, which achieves an excellent photoelectrochemical water splitting performance by additional triple modifications. The strategy paves a way for other photoelectrode materials to significantly improve their performance.
      PubDate: 2017-08-14T01:21:03.503967-05:
      DOI: 10.1002/adfm.201702428
       
  • A Flexible 3D Multifunctional MgO-Decorated Carbon Foam@CNTs Hybrid as
           Self-Supported Cathode for High-Performance Lithium-Sulfur Batteries
    • Authors: Mingwu Xiang; Hao Wu, Heng Liu, Ju Huang, Yifeng Zheng, Li Yang, Peng Jing, Yun Zhang, Shixue Dou, Huakun Liu
      Abstract: One of the critical challenges to develop advanced lithium-sulfur (Li-S) batteries lies in exploring a high efficient stable sulfur cathode with robust conductive framework and high sulfur loading. Herein, a 3D flexible multifunctional hybrid is rationally constructed consisting of nitrogen-doped carbon foam@CNTs decorated with ultrafine MgO nanoparticles for the use as advanced current collector. The dense carbon nanotubes uniformly wrapped on the carbon foam skeletons enhance the flexibility and build an interconnected conductive network for rapid ionic/electronic transport. In particular, a synergistic action of MgO nanoparticles and in situ N-doping significantly suppresses the shuttling effect via enhanced chemisorption of lithium polysulfides. Owing to these merits, the as-built electrode with an ultrahigh sulfur loading of 14.4 mg cm−2 manifests a high initial areal capacity of 10.4 mAh cm−2, still retains 8.8 mAh cm−2 (612 mAh g−1 in gravimetric capacity) over 50 cycles. The best cycling performance is achieved upon 800 cycles with an extremely low decay rate of 0.06% at 2 C. Furthermore, a flexible soft-packaged Li-S battery is readily assembled, which highlights stable electrochemical characteristics under bending and even folding. This cathode structural design may open up a potential avenue for practical application of high-sulfur-loading Li-S batteries toward flexible energy-storage devices.A 3D flexible multifunctional hybrid comprised of nitrogen-doped carbon foam@carbon nanotubes decorated with ultrafine MgO nanoparticles (CF@CNTs/MgO) is designed by a structural engineering strategy. This hybrid is used as the self-supported current collector for high-performance Li-S batteries with high sulfur-loading.
      PubDate: 2017-08-11T05:55:21.949651-05:
      DOI: 10.1002/adfm.201702573
       
  • 6-Mercaptopurine-Induced Fluorescence Quenching of Monolayer MoS2
           Nanodots: Applications to Glutathione Sensing, Cellular Imaging, and
           Glutathione-Stimulated Drug Delivery
    • Authors: Shih-Chiang Chen; Chang-Yu Lin, Tian-Lu Cheng, Wei-Lung Tseng
      Abstract: Molybdenum disulfide (MoS2) nanodots (NDs) with sulfur vacancies have been demonstrated to be suitable to conjugate thiolated molecules. However, thiol-induced fluorescence quenching of MoS2 NDs has been rarely explored. In this study, 6-mercaptopurine (6-MP) serves as an efficient quencher for the fluorescence of monolayer MoS2 (M-MoS2) NDs. 6-MP molecules are chemically adsorbed at the sulfur vacancy sites of the M-MoS2 NDs. The formed complexes trigger the efficient fluorescence quenching of the M-MoS2 NDs due to acceptor-excited photoinduced electron transfer. The presence of glutathione (GSH) efficiently triggers the release of 6-MP from the M-MoS2 NDs, thereby switching on the fluorescence of the M-MoS2 NDs. Thus, the 6-MP-M-MoS2 NDs are implemented as a platform for the sensitive and selective detection of GSH in erythrocytes and live cells. Additionally, thiolated doxorubicin (DOX-SH)-loaded M-MoS2 NDs (DOX-SH/M-MoS2 NDs) serve as GSH-responsive nanocarriers for DOX-SH delivery. In vitro studies reveal that the DOX-SH/M-MoS2 NDs exhibit efficient uptake by HeLa cells and greater cytotoxicity than free DOX-SH and DOX. In vivo study shows that GSH is capable of triggering the release of DOX-SH from M-MoS2 ND-based nanomaterials in mice. It is revealed that the DOX-SH/M-MoS2 NDs can be implemented for simultaneous drug delivery and fluorescence imaging.A series of thiol-loaded MoS2 nanodots (NDs) based on the attachment of thiol group on sulfur vacancy sites are fabricated. 6-mercaptopurie-conjugated MoS2 NDs are implemented as a platform for sensing glutathione in blood and live cells through in situ ligand exchange. Thiolated doxorubicin-conjugated MoS2 NDs serve as glutathione-responsive nanocarriers for simultaneous drug delivery and cellular imaging.
      PubDate: 2017-08-11T05:53:42.737483-05:
      DOI: 10.1002/adfm.201702452
       
  • Straightforward Immunosensing Platform Based on Graphene Oxide-Decorated
           Nanopaper: A Highly Sensitive and Fast Biosensing Approach
    • Authors: Nopchulee Cheeveewattanagul; Eden Morales-Narváez, Abdel-Rahim H. A. Hassan, José Francisco Bergua, Werasak Surareungchai, Mithran Somasundrum, Arben Merkoçi
      Abstract: Immunoassays are nowadays a crucial tool for diagnostics and drug development. However, they often involve time-consuming procedures and need at least two antibodies in charge of the capture and detection processes, respectively. This study reports a nanocomposite based on graphene oxide-coated nanopaper (GONAP) facilitating an advantageous immunosensing platform using a single antibody and without the need for washing steps. The hydrophilic, porous, and photoluminescence-quenching character of GONAP allows for the adsorption and quenching of photoluminescent quantum dots nanocrystals complexed with antibodies (Ab-QDs), enabling a ready-to-use immunosensing platform. The photoluminescence is recovered upon immunocomplex (antibody-antigen) formation which embraces a series of interactions (hydrogen bonding, electrostatic, hydrophobic, and Van der Waals interactions) that trigger desorption of the antigen-Ab-QD complex from GONAP surface. However, the antigen is then attached onto the GONAP surface by electrostatic interactions leading to a spacer (greater than ≈20 nm) between Ab-QDs and GONAP and thus hindering nonradiative energy transfer. It is demonstrated that this simple—yet highly sensitive—platform represents a virtually universal immunosensing approach by using small-sized and big-sized targets as model analytes, those are, human-IgG protein and Escherichia coli bacteria. In addition, the assay is proved effective in real matrices analysis, including human serum, poultry meat, and river water. GONAP opens the way to conceptually new paper-based devices for immunosensing, which are amenable to point of care applications and automated diagnostics.Graphene oxide-coated nanopaper is introduced as an immunosensing platform. This virtually universal immunoassay approach avoids washing steps and facilitates rapid analysis without compromising its sensitivity.
      PubDate: 2017-08-11T05:52:16.126779-05:
      DOI: 10.1002/adfm.201702741
       
  • Field-Induced n-Doping of Black Phosphorus for CMOS Compatible 2D Logic
           Electronics with High Electron Mobility
    • Authors: Yijun Xu; Jian Yuan, Kai Zhang, Yuan Hou, Qiu Sun, Yingming Yao, Shaojuan Li, Qiaoliang Bao, Han Zhang, Yuegang Zhang
      Abstract: Black phosphorus (BP) has been considered as a promising two-dimensional (2D) semiconductor beyond graphene owning to its tunable direct bandgap and high carrier mobility. However, the hole-transport-dominated characteristic limits the application of BP in versatile electronics. Here, we report a stable and complementary metal oxide semiconductor (COMS) compatible electron doping method for BP, which is realized with the strong field-induced effect from the K+ center of the silicon nitride (SixNy). An obvious change from pristine p-type BP to n type is observed after the deposit of the SixNy on the BP surface. This electron doping can be kept stable for over 1 month and capable of improving the electron mobility of BP towards as high as ~176 cm2 V–1 s–1. Moreover, high-performance in-plane BP p-n diode and further logic inverter were realized by utilizing the n-doping approach. The BP p-n diode exhibits a high rectifying ratio of ~104. And, a successful transfer of the output voltage from “High” to “Low” with very few voltage loss at various working frequencies were also demonstrated with the constructed BP inverter. Our findings paves the way for the success of COMS compatible technique for BP-based nanoelectronics.A stable and complementary metal oxide semiconductor (CMOS) compatible electron doping strategy for black phosphorus is realized with a field-induced effect. The effective electron doping with highly improved electron mobility enables the fabrication of high-performance logic devices, including a PN diode with rectifying ratio up to ≈104 and an inverter that is compatible with various driving frequencies.
      PubDate: 2017-08-11T05:51:52.096912-05:
      DOI: 10.1002/adfm.201702211
       
  • Nanoscale Optoregulation of Neural Stem Cell Differentiation by
           Intracellular Alteration of Redox Balance
    • Authors: Sara Hassanpour-Tamrin; Hossein Taheri, Mohammad Mahdi Hasani-Sadrabadi, S. Hamed Shams Mousavi, Erfan Dashtimoghadam, Mahdi Tondar, Ali Adibi, Alireza Moshaverinia, Amir Sanati Nezhad, Karl I. Jacob
      Abstract: Regulation of stem cell (SC) fate, a decision between self-renewal and differentiation, is of immense importance in regenerative medicine and has been proven to be a powerful stimulus regulating many cell functions influencing the SC fate. This study uses triphenylphosphonium-functionalized gold nanoparticles (TPP-AuNPs) to explore the interplay of intracellular electromagnetic (EM) exposure and the SC fate. Localized EM waves are generated inside neural stem cells (NSCs) to stimulate TPP-AuNPs (AuNPs), targeting the mitochondria through inducing reactive oxygen species and differentiating these cells into neurons. Following laser irradiation of TPP-AuNPs-transfected NSCs, their differentiation to neurons is monitored by tracing the relevant markers both at the genetic and protein levels. The electrophysiology technique is further used to examine the functionality of neurons. The results confirm that TPP-AuNPs subjected to electromotive forces have the potential to regulate cellular fate, although further investigations are still required to shed light on the mechanisms underlying the interaction of EM-stimulated TPP-AuNPs on cellular fate to design highly adjustable cell differentiation and reprogramming methods.Regulation of stem cell fate is a decision between self-renewal and differentiation, and it can be altered remotely. Here, functionalized gold nanoparticles are used to generate localized electromagnetic fields inside neural stem cells to stimulate their neural differentiation by inducing reactive oxygen species near the mitochondria.
      PubDate: 2017-08-11T01:56:42.133124-05:
      DOI: 10.1002/adfm.201701420
       
  • Neural Electrodes Based on 3D Organic Electroactive Microfibers
    • Authors: Jason B. Marroquin; Harold A. Coleman, Mary A. Tonta, Kun Zhou, Bjorn Winther-Jensen, James Fallon, Noel W. Duffy, Edwin Yan, Ammar A. Abdulwahid, Jacek J. Jasieniak, John S. Forsythe, Helena C. Parkington
      Abstract: Neural electrodes used for in vivo biomedical applications (e.g., prostheses, bionic implants) result in glial invasion, leading to the formation of a nonexcitable scar that increases the distance between neurons and electrode and increases the resistance to current flow. The result is progressive deterioration in the performance of stimulation or recording of neural activity and inevitable device failure. Also, electrodes with a 2D surface have a limited proximity to neurons. In the present study, a macroporous and fibrous 3D neural electrode is developed using poly-L-lactic acid fibrous membranes imbued with electroactive properties via a coating of the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT), using vapor phase polymerization. The electrical properties of the PEDOT-coated substrates are studied using sheet resistance and impedance. PEDOT electrode biocompatibility is assessed through in vitro assays using patch-clamp electrophysiology and calcium imaging of isolated and cultured rat hippocampal neurons. PEDOT fibers support robust normal functional development of neurons, including synaptic networking and communication. Stimulation and recording of activity in brain slices and from the surface of the brain using 3D-PEDOT fibrous electrodes are indistinguishable from recordings using conventional glass or platinum electrodes. In vivo studies reveal minimal reactive gliosis in response to electrode implantation.A macroporous and fibrous 3D neural electrode is developed using electrospun membranes imbued with electroactive properties via a coating of poly(3,4-ethylenedioxythiophene) (PEDOT). The PEDOT fibrous electrode supports robust normal functional development of neurons in vitro and is able to integrate into the brain with minimal inflammatory response and provide recordings of brain activity.
      PubDate: 2017-08-11T01:56:15.522576-05:
      DOI: 10.1002/adfm.201700927
       
  • Surface Features of Recombinant Spider Silk Protein eADF4(κ16)-Made
           Materials are Well-Suited for Cardiac Tissue Engineering
    • Authors: Jana Petzold; Tamara B. Aigner, Filip Touska, Katharina Zimmermann, Thomas Scheibel, Felix B. Engel
      Abstract: Cardiovascular diseases causing high morbidity and mortality represent a major socioeconomic burden. The primary cause of impaired heart function is often the loss of cardiomyocytes. Thus, novel therapies aim at restoring the lost myocardial tissue. One promising approach is cardiac tissue engineering. Previously, it is shown that Antheraea mylitta silk protein fibroin is a suitable material for cardiac tissue engineering, however, its quality is difficult to control. To overcome this limitation, the interaction of primary rat heart cells with engineered Araneus diadematus fibroin 4 (κ16) (eADF4(κ16)) is investigated here, which is engineered based on the sequence of ADF4 by replacing the glutamic acid residue in the repetitive unit of its core domain with lysine. The data demonstrate that cardiomyocytes, fibroblasts, endothelial cells, and smooth muscle cells attach well to eADF4(κ16) films on glass coverslips which provide an engineered surface with a polycationic character. Moreover, eADF4(κ16) films have, in contrast to fibronectin films, no hypertrophic effect but allow the induction of cardiomyocyte hypertrophy. Finally, cardiomyocytes grown on eADF4(κ16) films respond to pro-proliferative factors and exhibit proper cell-to-cell communication and electric coupling. Collectively, these data demonstrate that designed recombinant eADF4(κ16)-based materials are promising materials for cardiac tissue engineering.Engineered Araneus diadematus fibroin 4 (κ16) (eADF4(κ16)) is a recombinant protein engineered based on the sequence of ADF4. It is a positively charged material for cardiac tissue engineering that can be produced in large quantities providing the advantages of silk proteins such as biodegradability and low immunogenicity.
      PubDate: 2017-08-11T01:05:03.059948-05:
      DOI: 10.1002/adfm.201701427
       
  • Marangoni-Effect-Assisted Bar-Coating Method for High-Quality Organic
           Crystals with Compressive and Tensile Strains
    • Authors: Zhichao Zhang; Boyu Peng, Xudong Ji, Ke Pei, Paddy Kwok Leung Chan
      Abstract: Low-cost solution-shearing methods are highly desirable for deposition of organic semiconductor crystals over a large area. To enhance the rate of evaporation and deposition, elevated substrate temperature is commonly employed during shearing processes. However, the Marangoni flow induced by a temperature-dependent surface-tension gradient near the meniscus line shows negative effects on the deposited crystals and its electrical properties. In the current study, the Marangoni effect to improve the shearing process of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene for organic field-effect transistor (OFET) applications is utilized and regulated. By modifying the gradient of surface tension with different combinations of solvents, the mass transport of molecules is much more favorable, which largely enhances the deposition rate, reduces organic crystal thickness, enlarges grain sizes, and improves coverage. The average and highest mobility of OFETs can be increased up to 13.7 and 16 cm2 V−1 s−1. This method provides a simple deposition approach on a large scale, which allows to further fabricate large-area circuits, flexible displays, or bioimplantable sensors.The effect of surface-tension gradient on the fluid movement and molecular deposition is studied during solution shearing of organic semiconductor crystals. Ultrathin and uniform layers of crystals with large domain sizes are achieved by a novel Marangoni-effect-assisted bar-coating method, and the mobility of organic field-effect transistors can reach 16 cm2 V−1 s−1 with very good uniformity.
      PubDate: 2017-08-10T00:56:38.293133-05:
      DOI: 10.1002/adfm.201703443
       
  • Boronic Acid Decorated Defective Metal–Organic Framework Nanoreactors
           for High-Efficiency Carbohydrates Separation and Labeling
    • Authors: Guosheng Chen; Xu'an Fang, Qing Chen, Jin'ge Zhang, Zhensong Zhong, Jianqiao Xu, Fang Zhu, Gangfeng Ouyang
      Abstract: Separation and labeling are the crucial steps for the carbohydrates identification and detection in the important field of biochemistry, biomedicine, glycomics, and glycobiology. Herein, for the first time, a boronic acid decorated defective metal–organic framework (B-D-MI-100) nanoreactor is designed, which integrates fast separation and labeling of carbohydrates into one step. Without the sacrifice of internal room space, the incorporation of abundant functional boronic acid groups into the framework is achieved through metal–ligand–fragment coassembly strategy. And the novel solid phase orientation labeling approach performed within elaborate Cr based B-D-MIL-100 nanoreactor is facile to avoid the conformation transition of carbohydrates occurred in classical liquid-phase labeling. As a result, the novel approach presents several merits, including high separation efficiency (almost all of the incorporated boronic acid groups are available), much fast labeling reaction speed (labeling reaction time is decreased from 7 h to 3 min), high purity of the product, and three orders of magnitude lower applicable carbohydrate concentration for labeling. Thus, this new approach advances the idea to efficiently detect and identify trace carbohydrates in important fields such as glycomics and glycobiology.A novel nanoreactor integrating fast carbohydrates separation and labeling into one step is developed by using boronic acid decorated defective metal–organic framework. It exhibits several significant advantages, including high separation efficiency and ultrafast labeling speed, high purity of the product, and much lower applicable carbohydrate concentration.
      PubDate: 2017-08-10T00:56:04.396435-05:
      DOI: 10.1002/adfm.201702126
       
  • Improving Electrical Stability and Ideality in Organic Field-Effect
           Transistors by the Addition of Fullerenes: Understanding the Working
           Mechanism
    • Authors: Hung Phan; Michael J. Ford, Alexander T. Lill, Ming Wang, Guillermo C. Bazan, Thuc-Quyen Nguyen
      Abstract: Electrical instability and nonideality due to undesirable electron injection are often-encountered problems for high-mobility organic field-effect transistors (OFETs) with low-bandgap polymer semiconductors. Due to electron trapping and the resulting accumulation of negative charges on the silicon dioxide dielectric, transfer curves deviate from ideality characteristics and double-slopes are observed as the devices are operated for extended periods of time. One way to circumvent those is to use an electron-acceptor additive, such as fullerene and its derivatives. This work interprets the mechanisms of how fullerene derivatives suppress electron transport and electrical instability while maintaining high hole mobility in p-type OFETs. This study shows that hole transport of the active layer is uninterrupted upon the addition of the electron acceptors. Most importantly, the added fullerene derivatives out-compete SiO2 to acquire electrons that are injected into the polymers. Electrical instability and double-slope induced from electron trapping at SiO2 surface are thereby suppressed.The mechanisms of how fullerene derivatives suppress electron trapping on SiO2 and the consequent electrical instability and double slope, while maintaining high hole mobility in p-type organic field-effect transistors, are interpreted. First, hole transport of the active layer is uninterrupted upon the addition of the electron acceptors. Most importantly, the added fullerene derivatives out-compete SiO2 to acquire electrons that are injected into the polymers.
      PubDate: 2017-08-09T02:41:39.306239-05:
      DOI: 10.1002/adfm.201701358
       
  • Black Phosphorus Nanoparticles Potentiate the Anticancer Effect of
           Oxaliplatin in Ovarian Cancer Cell Line
    • Authors: Michaela Fojtů; Xinyi Chia, Zdeněk Sofer, Michal Masařík, Martin Pumera
      Abstract: During the past few years, growing attention has been paid to black phosphorus (BP) and its unique optical, electrical, and catalytic properties. Furthermore, BP has proven to be biocompatible and biodegradable; qualities that present new opportunities for its utilization in the field of life sciences. However, despite all its suitable properties and applicability, its utilization in biomedicine is still in its infancy. This study reports on the synthesis of black phosphorus nanoparticles (BP NPs) and exploration of thier applicability in targeted drug delivery. BP NPs are loaded with platinum agents—cisplatin and oxaliplatin—and subjected to in vitro evaluation of targeted drug delivery. The BP NPs are not only able to load the investigated platinum derivatives on their surfaces, but also to transfer the therapeutic cargo to target specific tissue and to combine their effect with oxaliplatin, which leads to further potentiation of the anticancer effect.Black phosphorus nanoparticles are surface-loaded with platinum derivatives, investigated herein, to transfer a therapeutic cargo to a specific target tissue, to combine their effect with oxaliplatin, leading to further potentiation of the anticancer effect.
      PubDate: 2017-08-07T07:16:34.942466-05:
      DOI: 10.1002/adfm.201701955
       
  • Enhanced Performance of P2-Na0.66(Mn0.54Co0.13Ni0.13)O2 Cathode for
           Sodium-Ion Batteries by Ultrathin Metal Oxide Coatings via Atomic Layer
           Deposition
    • Authors: Karthikeyan Kaliyappan; Jian Liu, Biwei Xiao, Andrew Lushington, Ruying Li, Tsun-Kong Sham, Xueliang Sun
      Abstract: Sodium-ion batteries are widely considered as promising energy storage systems for large-scale applications, but their relatively low energy density hinders further practical applications. Developing high-voltage cathode materials is an effective approach to increase the overall energy density of sodium-ion batteries. When cut-off voltage is elevated over 4.3 V, however, the cathode becomes extremely unstable due to structural transformations as well as metal dissolution into the electrolytes. In this work, the cyclic stability of P2-Na0.66(Mn0.54Co0.13Ni0.13)O2 (MCN) electrode at a cut-off voltage of 4.5 V is successfully improved by using ultrathin metal oxide surface coatings (Al2O3, ZrO2, and TiO2) deposited by an atomic layer deposition technique. The MCN electrode coated with the Al2O3 layer exhibits higher capacity retention among the MCN electrodes. Moreover, the rate performance of the MCN electrode is greatly improved by the metal oxide coatings in the order of TiO2 < Al2O3 < ZrO2, due to increased fracture toughness and electrical conductivity of the metal oxide coating layers. A ZrO2-coated MCN electrode shows a discharge capacity of 83 mAh g−1 at 2.4 A g−1, in comparison to 61 mAh g−1 for a pristine MCN electrode. Cyclic voltammetry and electrochemical impedance analysis disclose the reduced charge transfer resistance from 1421 to 760.2 Ω after cycles, suggesting that the metal oxide coating layer can effectively minimize the undesirable phase transition, buffer inherent stress and strain between the binder, cathode, and current collector, and avoid volumetric changes, thus increasing the cyclic stability of the MCN electrode.Different metal oxide coatings by atomic layer deposition are employed to stabilize the electrochemical stability of P2-Na0.66(Mn0.54Co0.13Ni0.13)O2 cathodes for sodium-ion batteries. The cyclic stability is extremely enhanced after the coating process. Moreover, the P2 materials coated with ZrO2 have improved rate performance with TiO2, Al2O3 layer, due to increased fracture toughness and electrical conductivity of ZrO2 layers.
      PubDate: 2017-08-07T07:15:41.320463-05:
      DOI: 10.1002/adfm.201701870
       
  • Shape-Reconfigurable Aluminum–Air Batteries
    • Authors: Sangjin Choi; Daehee Lee, Gwangmook Kim, Yoon Yun Lee, Bokyung Kim, Jooho Moon, Wooyoung Shim
      Abstract: The battery shape is a critical limiting factor affecting foreseeable energy storage applications. In particular, deformable metal–air battery systems can offer low cost, low flammability, and high capacity, but the fabrication of such metal–air batteries remains challenging. Here, it is shown that a shape-reconfigurable-material approach, in which the deformable components composed of micro- and nanoscale composites are assembled, is suitable for constructing polymorphic metal–air batteries. By employing an aluminum foil and an adhesive carbon composite placed on a cellulose scaffold as a substrate, an aluminum–air battery that can be deformed to an unprecedented high level, e.g., via expanding, folding, stacking, and crumpling, can be realized. This significant deformability results in a specific capacity of 128 mA h g−1 (496 mA h g−1 per cell; based on the mass of consumed aluminum) and a high output voltage (10.3 V) with 16 unit battery cells connected in series. The resulting battery can endure significant geometrical distortions such as 3D expanding and twisting, while the electrochemical performance is preserved. This work represents an advancement in deformable aluminum–air batteries using the shape-reconfigurable-material concept, thus establishing a paradigm for shape-reconfigurable batteries with exceptional mechanical functionalities.Shape-reconfigurable batteries that lead to 2D and 3D polymorphed states while preserving electrochemical functionality are developed. Aluminum–air batteries composed of an aluminum foil and a carbon composite on a cellulose scaffold are adopted as a platform, which represents an advancement in deformable batteries using the shape-reconfigurable-material concept, establishing a paradigm for shape-reconfigurable batteries with exceptional mechanical functionalities.
      PubDate: 2017-08-07T07:13:58.743748-05:
      DOI: 10.1002/adfm.201702244
       
  • Rationally Designed Donor–Acceptor Random Copolymers with Optimized
           Complementary Light Absorption for Highly Efficient All-Polymer Solar
           Cells
    • Authors: Sang Woo Kim; Joonhyeong Choi, Thi Thu Trang Bui, Changyeon Lee, Changsoon Cho, Kwangmin Na, Jihye Jung, Chang Eun Song, Biwu Ma, Jung-Yong Lee, Won Suk Shin, Bumjoon J. Kim
      Abstract: Most of the high-performance all-polymer solar cells (all-PSCs) reported to date are based on polymer donor and polymer acceptor pairs with largely overlapped light absorption properties, which seriously limits the efficiency of all-PSCs. This study reports the development of a series of random copolymer donors possessing complementary light absorption with the naphthalenediimide-based polymer acceptor P(NDI2HD-T2) for highly efficient all-PSCs. By controlling the molar ratio of the electron-rich benzodithiophene (BDTT) and electron-deficient fluorinated-thienothiophene (TT-F) units, a series of polymer donors with BDTT:TT-F ratios of 1:1 (P1), 3:1 (P2), 5:1 (P3), and 7:1 (P4) are prepared. The synthetic control of polymer composition allows for precise tuning of the light absorption properties of these new polymer donors, enabling optimization of light absorption properties to complement those of the P(NDI2HD-T2) acceptor. Copolymer P1 is found to be the optimal polymer donor for the fullerene-based solar cells due to its high light absorption, whereas the highest power conversion efficiency of 6.81% is achieved for the all-PSCs with P3, which has the most complementary light absorption with P(NDI2HD-T2).A series of poly(benzodithiophene-r-fluorinated-thienothiophene) [P(BDTT-r-TT-F)] random copolymers with tunable light absorption characteristics are developed by controlling the ratios of electron-rich BDTT and electron-deficient TT-F units. All-polymer solar cells (all-PSCs) fabricated from these polymer donors and the P(NDI2HD-T2) acceptor achieve efficiencies of up to 6.8% by optimizing the complementary light absorption of the polymer donor and acceptor.
      PubDate: 2017-08-07T07:13:00.846382-05:
      DOI: 10.1002/adfm.201703070
       
  • General Synthesis of Dual Carbon-Confined Metal Sulfides Quantum Dots
           Toward High-Performance Anodes for Sodium-Ion Batteries
    • Authors: Ziliang Chen; Renbing Wu, Miao Liu, Hao Wang, Hongbin Xu, Yanhui Guo, Yun Song, Fang Fang, Xuebin Yu, Dalin Sun
      Abstract: Sponge-like composites assembled by cobalt sulfides quantum dots (Co9S8 QD), mesoporous hollow carbon polyhedral (HCP) matrix, and a reduced graphene oxide (rGO) wrapping sheets are synthesized by a simultaneous thermal reduction, carbonization, and sulfidation of zeolitic imidazolate frameworks@GO precursors. Specifically, Co9S8 QD with size less than 4 nm are homogenously embedded within HCP matrix, which is encapsulated in macroporous rGO, thereby leading to the double carbon-confined hierarchical composites with strong coupling effect. Experimental data combined with density functional theory calculations reveal that the presence of coupled rGO not only prevents the aggregation and excessive growth of particles, but also expands the lattice parameters of Co9S8 crystals, enhancing the reactivity for sodium storage. Benefiting from the hierarchical porosity, conductive network, structural integrity, and a synergistic effect of the components, the sponge-like composites used as binder-free anodes manifest outstanding sodium-storage performance in terms of excellent stable capacity (628 mAh g−1 after 500 cycles at 300 mA g−1) and exceptional rate capability (529, 448, and 330 mAh g−1 at 1600, 3200, and 6400 mA g−1). More importantly, the synthetic method is very versatile and can be easily extended to fabricate other transition-metal-sulfides-based sponge-like composites with excellent electrochemical performances.Sponge-like composites assembled by Co9S8 quantum dots, hollow carbon polyhedra, and 3D reduced graphene oxide (GO) network are fabricated by a simultaneous thermal reduction, carbonization, and sulfidation of zeolitic imidazolate frameworks@GO precursors. Benefiting from the hierarchical porosity, conductive network, structural integrity, and synergistic effect of components, the composites used as binder-free anodes exhibit high specific capacity, good rate performance, and outstanding cycling stability in sodium-ion batteries.
      PubDate: 2017-08-07T07:12:15.825451-05:
      DOI: 10.1002/adfm.201702046
       
  • The Enabling Electronic Motif for Topological Insulation in ABO3
           Perovskites
    • Authors: Xiuwen Zhang; Leonardo B. Abdalla, Qihang Liu, Alex Zunger
      Abstract: Stable oxide topological insulators (TIs) have been sought for years, but none have been found; whereas heavier (selenides, tellurides) chalcogenides can be TIs. The basic contradiction between topological insulation and thermodynamic stability is pointed out, offering a narrow window of opportunity. The electronic motif is first identified and can achieve topological band inversion in ABO3 as a lone-pair, electron-rich B atom (e.g., Te, I, Bi) at the octahedral site. Then, twelve ABO3 compounds are designed in the assumed cubic perovskite structure, which satisfy this electronic motif and are indeed found by density function theory calculations to be TIs. Next, it is illustrated that poorly screened ionic oxides with large inversion energies undergo energy-lowering atomic distortions that destabilize the cubic TI phase and remove band inversion. The coexistence windows of topological band inversion and structure stability can nevertheless be expanded under moderate pressures (15 and 35 GPa, respectively, for BaTeO3 and RbIO3). This study traces the principles needed to design stable oxide topological insulators at ambient pressures as a) a search for oxides with small inversion energies; b) design of large inversion-energy oxide TIs that can be stabilized by pressure; and c) a search for covalent oxides where TI-removing atomic displacements can be effectively screened out.ABO3 perovskites where B is an electron-rich element would be topological insulators if the cubic structure could be stabilized. But in such band-inverted topological insulators, depopulation of bonding valence states and occupation of antibonding conduction states raises the energy, leading, in some cases, to structural distortions that are poorly shielded in oxides. In the distorted structure the band inversion is reversed.
      PubDate: 2017-08-07T07:10:56.855133-05:
      DOI: 10.1002/adfm.201701266
       
  • “Tissue Papers” from Organ-Specific Decellularized
           Extracellular Matrices
    • Authors: Adam E. Jakus; Monica M. Laronda, Alexandra S. Rashedi, Christina M. Robinson, Chris Lee, Sumanas W. Jordan, Kyle E. Orwig, Teresa K. Woodruff, Ramille N. Shah
      Abstract: Using an innovative, tissue-independent approach to decellularized tissue processing and biomaterial fabrication, the development of a series of “tissue papers” derived from native porcine tissues/organs (heart, kidney, liver, muscle), native bovine tissue/organ (ovary and uterus), and purified bovine Achilles tendon collagen as a control from decellularized extracellular matrix particle ink suspensions cast into molds is described. Each tissue paper type has distinct microstructural characteristics as well as physical and mechanical properties, is capable of absorbing up to 300% of its own weight in liquid, and remains mechanically robust (E = 1–18 MPa) when hydrated; permitting it to be cut, rolled, folded, and sutured, as needed. In vitro characterization with human mesenchymal stem cells reveals that all tissue paper types support cell adhesion, viability, and proliferation over four weeks. Ovarian tissue papers support mouse ovarian follicle adhesion, viability, and health in vitro, as well as support, and maintain the viability and hormonal function of nonhuman primate and human follicle-containing, live ovarian cortical tissues ex vivo for eight weeks postmortem. “Tissue papers” can be further augmented with additional synthetic and natural biomaterials, as well as integrated with recently developed, advanced 3D-printable biomaterials, providing a versatile platform for future multi-biomaterial construct manufacturing.This work describes a new, chemical-independent, comprehensive approach for fabricating tissue- and organ-specific, decellularized matrix-based biomaterials: “tissue papers” (TPs). TPs are biocompatible, bioactive, surgically friendly, and compatible with existing, new 3D-printable biomaterials.
      PubDate: 2017-08-07T02:00:02.948744-05:
      DOI: 10.1002/adfm.201700992
       
  • Novel p–p Heterojunctions Self-Powered Broadband Photodetectors with
           Ultrafast Speed and High Responsivity
    • Authors: Pingping Yu; Kai Hu, Hongyu Chen, Lingxia Zheng, Xiaosheng Fang
      Abstract: Novel inorganic/organic self-powered UV–vis photodetectors based on single Se microtube and conducting polymers—polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT)—are fabricated. The conducting polymers are directly coated on the surface of a single Se microtube via a facile and low-cost in situ polymerization method. The integrated Se/PANI photodetector with 45-nm-thick PANI layer shows excellent self-powered behavior under UV–vis light illumination. In particular, it exhibits high on/off ratio of 1.1 × 103, responsivity (120 mA W−1), large detectivity (3.78 × 1011 Jones), and ultrafast response speed (rise time of 4.5 µs and fall time of 2.84 ms) at zero bias at 610 nm (0.434 mW cm−2)-light illumination. Moreover, the individual Se/PPy and Se/PEDOT self-powered photodetectors also exhibit fast and stable responses, including responsivity of 70 and 5.5 mA W−1, rise time of 0.35 and 1.00 ms, fall time of 16.97 and 9.78 ms, respectively. Given the simple device architecture and low cost fabrication process, this work provides a promising way to fabricate inorganic/organic, high-performance, self-powered photodetectors.Novel individual inorganic/organic heterojunctions of Se microtube/polyaniline, polypyrrole, and poly (3,4-ethylenedioxythiophene) are synthesized, and the integrated Se/polyaniline photodetector exhibits self-powered broadband characteristics, including high on/off ratio of 1.1 × 103, responsibility (120 mA W−1), large detectivity (3.78 × 1011 Jones), and ultrafast response speed (rise time of 4.5 µs and fall time of 2.84 ms) at zero bias at 610 nm (0.434 mW cm−2)-light illumination.
      PubDate: 2017-08-04T09:17:45.744693-05:
      DOI: 10.1002/adfm.201703166
       
  • Multifunctional Electrode Design Consisting of 3D Porous Separator
           Modulated with Patterned Anode for High-Performance Dual-Ion Batteries
    • Authors: Songquan Zhang; Meng Wang, Zhiming Zhou, Yongbing Tang
      Abstract: Searching for low-cost and high-capacity electrode materials such as metal anodes is of important significance for the development of new generation rechargeable batteries. However, metal anodes always suffer from severe volume expansion/contraction during a repeated electrochemical alloying/dealloying process. In this study, a novel concept about modifying metal-anodes-based battery construction with a multifunctional electrode (ME) design is provided. The ME consists of a 3D porous separator that is modulated with a patterned aluminum anode, which simultaneously works as a current collector, anode material, and separator in a dual-ion battery (DIB). The 3D porous separator not only enables the ME to possess significantly improved electrolyte uptake and retention capabilities, but also acts as a protecting layer to restrict the surface pulverization of the Al anode. The ME-DIB displays remarkably enhanced cell performances, including excellent cycling stability with 92.4% capacity retention after 1000 cycles at a current density of 2 C, and superior rate performance with 80.7% capacity retention at 10 C.A multifunctional electrode (ME) consisting of a three-dimensional (3D) porous separator is reported that is modulated with a patterned aluminum anode, which simultaneously works as a current collector, anode material, and separator for a dual-ion battery (DIB). The 3D porous separator enables the ME significantly improved electrolyte uptake and retention capabilities, but also acts as a protecting layer to restrict pulverization of the Al anode. The ME-DIB displays excellent cycling stability and superior rate performance.
      PubDate: 2017-08-04T09:16:44.562776-05:
      DOI: 10.1002/adfm.201703035
       
  • Proton Conduction in a Tyrosine-Rich Peptide/Manganese Oxide Hybrid
           Nanofilm
    • Authors: Jaehun Lee; Ik Rang Choe, Young-O Kim, Seok Daniel Namgung, Kyoungsuk Jin, Hyo-Yong Ahn, Taehoon Sung, Jang-Yeon Kwon, Yoon-Sik Lee, Ki Tae Nam
      Abstract: Proton conduction is an essential process that regulates an integral part of several enzymatic catalyses and bioenergetics. Proton flows in biological entities are sensitively controlled by several mechanisms. To understand and manipulate proton conduction in biosystems, several studies have investigated bulk proton conduction in biomaterials such as polyaspartic acid, collagen, reflectin, serum albumin mats, and eumelanin. However, little is known about the bulk proton conductivity of short peptides and their sequence-dependent behavior. Here, this paper focuses on a short tyrosine-rich peptide that has redox-active and cross-linkable phenol groups. The spin-coated peptide nanofilm is immersed in potassium permanganate solution to induce cross-linking and oxidation, simultaneously leading to hybridization with manganese oxide (MnOx). The peptide/MnOx hybrid nanofilm can efficiently transport protons, and its proton conductivity is ≈18.6 mS cm−1 at room temperature. This value is much higher than that of biomaterials and comparable to those of other synthetic proton-conducting materials. These results suggest that peptide-based hybrid materials can be a promising new class of proton conductor.A new class of hybrid proton conductor composed of tyrosine-rich peptide and manganese oxide is synthesized. Electrical measurements and isotope analysis reveal that the main charge carrier of the hybrid film is a proton from water vapor. Interestingly, cross-linking and oxidation of tyrosine simultaneously lead to hybridization with MnOx, resulting in strong synergetic effects on proton conduction.
      PubDate: 2017-08-04T01:13:00.989989-05:
      DOI: 10.1002/adfm.201702185
       
  • Assessment of Novel Long-Lasting Ceria-Stabilized Zirconia-Based Ceramics
           with Different Surface Topographies as Implant Materials
    • Authors: Brigitte Altmann; Lamprini Karygianni, Ali Al-Ahmad, Frank Butz, Maria Bächle, Erik Adolfsson, Tobias Fürderer, Nicolas Courtois, Paola Palmero, Marie Follo, Jérôme Chevalier, Thorsten Steinberg, Ralf Joachim Kohal
      Abstract: The development of long-lasting zirconia-based ceramics for implants, which are not prone to hydrothermal aging, is not satisfactorily solved. Therefore, this study is conceived as an overall evaluation screening of novel ceria-stabilized zirconia–alumina–aluminate composite ceramics (ZA8Sr8-Ce11) with different surface topographies for use in clinical applications. Ceria-stabilized zirconia is chosen as the matrix for the composite material, due to its lower susceptibility to aging than yttria-stabilized zirconia (3Y-TZP). This assessment is carried out on three preclinical investigation levels, indicating an overall biocompatibility of ceria-stabilized zirconia-based ceramics, both in vitro and in vivo. Long-term attachment and mineralized extracellular matrix (ECM) deposition of primary osteoblasts are the most distinct on porous ZA8Sr8-Ce11p surfaces, while ECM attachment on 3Y-TZP and ZA8Sr8-Ce11 with compact surface texture is poor. In this regard, the animal study confirms the porous ZA8Sr8-Ce11p to be the most favorable material, showing the highest bone-to-implant contact values and implant stability post implantation in comparison with control groups. Moreover, the microbiological evaluation reveals no favoritism of biofilm formation on the porous ZA8Sr8-Ce11p when compared to a smooth control surface. Hence, together with the in vitro in vivo assessment analogy, the promising clinical potential of this novel ZA8Sr8-Ce11 as an implant material is demonstrated.An overall evaluation screening of a novel ceria-stabilized zirconia–alumina–aluminate composite ceramic with different surface topographies for use in clinical applications is presented. By assessing three preclinical investigation levels, namely human cell cultures, an animal model, and salivary bacteria, the promising clinical potential of this novel composite ceramic in combination with a porous surface structure as an implant material is demonstrated.
      PubDate: 2017-08-04T01:09:17.374551-05:
      DOI: 10.1002/adfm.201702512
       
  • Nanostructured Metal Chalcogenides for Energy Storage and Electrocatalysis
    • Authors: Yu Zhang; Qian Zhou, Jixin Zhu, Qingyu Yan, Shi Xue Dou, Wenping Sun
      Abstract: Energy storage and conversion technologies are vital to the efficient utilization of sustainable renewable energy sources. Rechargeable lithium-ion batteries (LIBs) and the emerging sodium-ion batteries (SIBs) are considered as two of the most promising energy storage devices, and electrocatalysis processes play critical roles in energy conversion techniques that achieve mutual transformation between renewable electricity and chemical energies. It has been demonstrated that nanostructured metal chalcogenides including metal sulfides and metal selenides show great potential for efficient energy storage and conversion due to their unique physicochemical properties. In this feature article, the recent research progress on nanostructured metal sulfides and metal selenides for application in SIBs/LIBs and hydrogen/oxygen electrocatalysis (hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction) is summarized and discussed. The corresponding electrochemical mechanisms, critical issues, and effective strategies towards performance improvement are presented. Finally, the remaining challenges and perspectives for the future development of metal chalcogenides in the energy research field are proposed.Metal chalcogenides including metal sulfides and selenides are intensively studied in the energy field due to their unique physicochemical properties. In this Review, specific attention is given to their state-of-the-art research progress in sodium-ion batteries, lithium-ion batteries, and electrocatalysis hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction.
      PubDate: 2017-08-04T01:08:36.143793-05:
      DOI: 10.1002/adfm.201702317
       
  • Superhydrophobic, Reversibly Elastic, Moldable, and Electrospun (SupREME)
           Fibers with Multimodal Functions: From Oil Absorbents to Local Drug
           Delivery Adjuvants
    • Authors: Slgirim Lee; Byeonggwan Kim, Seung-Hyun Kim, Eunkyoung Kim, Jae-Hyung Jang
      Abstract: Surface hydrophobicity has served as a core means for governing the spatial behaviors of numerous substances depending on their affinities to oil or aqueous phases. Exploiting systems that can maximize hydrophobic features contributes to the development of versatile supports capable of spatially separating, guiding, or protecting target materials in defined manners. Herein, superhydrophobic, reversibly elastic, moldable, and electrospun (SupREME) fibers, which exhibit multimodal functions for arranging spatial responses of substances with distinct affinities to oil phases, are fabricated by coaxially electrospinning polysulfone and poly(glycerol sebacate) (PGS), followed by a thermal process. The exterior PSF layers enable volumetric expansion of the fibers, further reinforcing the overall superhydrophobicity (contact angles>150°). The elastic core PGS networks confer reversibly compressible properties (>100 cycles) to the fibers, ultimately enhancing their hydrophobic performance and extending their durability. The SupREME fibers demonstrate superiorities as absorbents for selectively separating oil-based substances, sealants for blocking the leakage of aqueous fluids, and adjuvants for temporarily enhancing the local residence of drugs by repelling ambient fluidic environments. The SupREME fibers can be versatile platforms in many applications that require the spatial regulation of specific substances with affinities to oil or water phases, ranging from environmental industries to medical fields.Superhydrophobic, reversibly elastic, moldable, electrospun fibers with 3D fluffy geometries are fabricated by coaxially electrospinning two distinct polymers: hydrophobic polysulfone and elastic poly(glycerol sebacate). The SupREME fibers demonstrate multimodal functions as oil absorbents, sealants for blocking water passage/leakage, and adjuvants for extending the local residence of hydrophilic drugs under ambient fluid environments, confirming the broad spectrum of their potential applications.
      PubDate: 2017-08-04T01:06:30.086511-05:
      DOI: 10.1002/adfm.201702310
       
  • Ordered Porous Electrodes by Design: Toward Enhancing the Effective
           Utilization of Platinum in Electrocatalysis
    • Authors: Brandy K. Pilapil; Julia van Drunen, Yoseif Makonnen, Diane Beauchemin, Gregory Jerkiewicz, Byron D. Gates
      Abstract: Platinum-nanoparticle-functionalized, ordered, porous support electrodes are prepared and characterized as a potential new class of oxygen reduction reaction (ORR) electrocatalysts. This study aims to develop electrode materials that enhance the effective utilization of Pt in electrocatalytic reactions through improved mass transport properties, high Pt mass specific surface area, and increased Pt electrochemical stability. The electrodes are prepared using modular sacrificial templates, producing a uniform distribution of Pt nanoparticles inside ordered porous Au electrodes. This method can be further fine-tuned to optimize the architecture for a range of characteristics, such as varying nanoparticle properties, pore size, or support material. The Pt-coated Au, ordered, porous electrodes exhibit several improved characteristics, such as enhanced Pt effective utilization for ORR electrocatalysis. This includes a nearly twofold increase in Pt mass specific surface area over other ultrathin designs, superior mass transport properties in comparison to traditional catalyst layers of C black supported Pt nanoparticles mixed with ionomer, good methanol tolerance and exceptional stability toward Pt chemical and/or electrochemical dissolution through interfacial interactions with Au. The methods to prepare Pt-coated ordered porous electrodes can be extended to other architectures for enhanced catalyst utilization and improved performance of Pt in electrochemical processes.The preparation and electrocatalytic properties of Pt nanoparticles coated on ordered porous gold electrodes are demonstrated as a route to Pt electrocatalysts with enhanced effective utilization of Pt. These materials display good mass transport, high electrochemical stability, and a large Pt mass specific surface area in comparison to other ultrathin Pt electrocatalyst designs. The method established here for electrode preparation can be readily tuned to seek further correlations between electrocatalyst design and performance.
      PubDate: 2017-08-04T01:02:31.398472-05:
      DOI: 10.1002/adfm.201703171
       
  • 3D Self-Supported Fe-Doped Ni2P Nanosheet Arrays as Bifunctional Catalysts
           for Overall Water Splitting
    • Authors: Yingjie Li; Haichuan Zhang, Ming Jiang, Qian Zhang, Peilei He, Xiaoming Sun
      Abstract: The development of highly efficient bifunctional electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial for improving the efficiency of overall water splitting, but still remains challenging issue. Herein, 3D self-supported Fe-doped Ni2P nanosheet arrays are synthesized on Ni foam by hydrothermal method followed by in situ phosphorization, which serve as bifunctional electrocatalysts for overall water splitting. The as-synthesized (Ni0.33Fe0.67)2P with moderate Fe doping shows an outstanding OER performance, which only requires an overpotential of ≈230 mV to reach 50 mA cm−2 and is more efficient than the other Fe incorporated Ni2P electrodes. In addition, the (Ni0.33Fe0.67)2P exhibits excellent activity toward HER with a small overpotential of ≈214 mV to reach 50 mA cm−2. Furthermore, an alkaline electrolyzer is measured using (Ni0.33Fe0.67)2P electrodes as cathode and anode, respectively, which requires cell voltage of 1.49 V to reach 10 mA cm−2 as well as shows excellent stability with good nanoarray construction. Such good performance is attributed to the high intrinsic activity and superaerophobic surface property.3D self-supported Fe-doped Ni2P nanosheet arrays are fabricated by hydrothermal method and in situ phosphorization. The performance of the nanosheet arrays toward overall water splitting depends on the Fe doping ratio. An alkaline electrolyzer using two identical (Ni0.33Fe0.67)2P nanosheet arrays electrodes can operate at 10 mA cm-2 under 1.49 V.
      PubDate: 2017-08-04T01:02:14.008104-05:
      DOI: 10.1002/adfm.201702513
       
  • High-Performance Wearable Micro-Supercapacitors Based on
           Microfluidic-Directed Nitrogen-Doped Graphene Fiber Electrodes
    • Authors: Guan Wu; Pengfeng Tan, Xingjiang Wu, Lu Peng, Hengyang Cheng, Cai-Feng Wang, Wei Chen, Ziyi Yu, Su Chen
      Abstract: Fiber-shaped micro-supercapacitors (micro-SCs) have attracted enormous interest in wearable electronics due to high flexibility and weavability. However, they usually present a low energy density because of inhomogeneity and less pores. Here, we demonstrate a microfluidic-directed strategy to synthesize homogeneous nitrogen-doped porous graphene fibers. The porous fibers-based micro-SCs utilize solid-state phosphoric acid/polyvinyl alcohol (H3PO4/PVA) and 1-ethyl-3-methylimidazolium tetrafluoroborate/poly(vinylidenefluoride-co-hexafluoropropylene) (EMIBF4/PVDF-HFP) electrolytes, which show significant improvements in electrochemical performances. Ultralarge capacitance (1132 mF cm−2), high cycling-stability, and long-term bending-durability are achieved based on H3PO4/PVA. Additionally, high energy densities of 95.7–46.9 µWh cm−2 at power densities of 1.5–15 W cm−2 are obtained in EMIBF4/PVDF-HFP. The key to higher performances stems from microfluidic-controlled fibers with a uniformly porous network, large specific surface area (388.6 m2 g−1), optimal pyridinic nitrogen (2.44%), and high electric conductivity (30785 S m−1) for faster ion diffusion and flooding accommodation. By taking advantage of these remarkable merits, this study integrates micro-SCs into flexible and fabric substrates to power audio–visual electronics. The main aim is to clarify the important role of microfluidic techniques toward the architecture of electrodes and promote development of wearable electronics.Novel fiber-shaped micro-supercapacitors are based on nitrogen-doped porous graphene fibers via a microfluidic technique. Owing to the microfluidic technique creating a uniform environment for fiber production, the fibers present a uniform porous network, large specific surface area, high electrical conductivity, and optimal nitrogen-active sites, which endow micro-supercapacitors higher electrochemical performance to successfully power audio–visual electronics.
      PubDate: 2017-08-04T01:01:46.934925-05:
      DOI: 10.1002/adfm.201702493
       
  • Experimental and Theoretical Studies of Serpentine Interconnects on
           Ultrathin Elastomers for Stretchable Electronics
    • Authors: Taisong Pan; Matt Pharr, Yinji Ma, Rui Ning, Zheng Yan, Renxiao Xu, Xue Feng, Yonggang Huang, John A. Rogers
      Abstract: Integrating deformable interconnects with inorganic functional materials establishes a path to high-performance stretchable electronics. A number of applications demand that these systems sustain large deformations under repetitive loading. In this manuscript, the influence of the elastomeric substrate on the stretchability of serpentine interconnects is investigated theoretically and experimentally. Finite element analyses (FEA) reveal a substantial increase in the elastic stretchability with reductions in substrate thickness. Low-cycle fatigue tests confirm this trend by examining the stretch required to form fatigue cracks associated with plastic deformation. To elucidate the mechanics governing this phenomenon, the buckling behaviors of deformed serpentine interconnects on substrates of various thicknesses are examined. The analytical model and FEA simulations suggest a change in the buckling mode from local wrinkling to global buckling below a critical thickness of the substrate. Scanning electron microscope and 3D optical profiler studies verify this transition in buckling behavior. The global buckling found in thin substrates accommodates large stretching prior to plastic deformation of the serpentines, thereby drastically enhancing the stretchability of these systems.A competition between the length of the straight segment of an interconnect and a critical length governed by the thickness of substrate determines the buckling mode of serpentine interconnects on elastomeric substrates, resulting in a significant increase in the elastic stretchability of the interconnects by reducing substrate thickness.
      PubDate: 2017-08-04T01:00:43.348586-05:
      DOI: 10.1002/adfm.201702589
       
  • Near-Infrared and Short-Wavelength Infrared Photodiodes Based on
           Dye–Perovskite Composites
    • Authors: Qianqian Lin; Zhiping Wang, Margaret Young, Jay B. Patel, Rebecca L. Milot, Laura Martinez Maestro, Richard R. Lunt, Henry J. Snaith, Michael B. Johnston, Laura M. Herz
      Abstract: Organohalide perovskites have emerged as promising light-sensing materials because of their superior optoelectronic properties and low-cost processing methods. Recently, perovskite-based photodetectors have successfully been demonstrated as both broadband and narrowband varieties. However, the photodetection bandwidth in perovskite-based photodetectors has so far been limited to the near-infrared regime owing to the relatively wide band gap of hybrid organohalide perovskites. In particular, short-wavelength infrared photodiodes operating beyond 1 µm have not yet been realized with organohalide perovskites. In this study, narrow band gap organic dyes are combined with hybrid perovskites to form composite films as active photoresponsive layers. Tuning the dye loading allows for optimization of the spectral response characteristics and excellent charge-carrier mobilities near 11 cm2 V−1 s−1, suggesting that these composites combine the light-absorbing properties or IR dyes with the outstanding charge-extraction characteristics of the perovskite. This study demonstrates the first perovskite photodiodes with deep near-infrared and short-wavelength infrared response that extends as far as 1.6 µm. All devices are solution-processed and exhibit relatively high responsivity, low dark current, and fast response at room temperature, making this approach highly attractive for next-generation light-detection techniques.Perovskite photodiodes with broadband photoresponse covering the visible, near-infrared (NIR), and short-wavelength-infrared (SWIR) regimes are achieved based on dye–perovskite composites. Dyes with small band gap extend the photon absorption up to the SWIR regime, and perovskite crystals enhance the charge transport and extraction. Prototype NIR and SWIR photodiodes exhibit high responsivity, low dark current and noise, and fast photoresponse.
      PubDate: 2017-08-04T00:56:25.961103-05:
      DOI: 10.1002/adfm.201702485
       
  • Scalable Nanowire Photonic Crystals: Molding the Light Emission of InGaN
    • Authors: Yong-Ho Ra; Roksana Tonny Rashid, Xianhe Liu, Jaesoong Lee, Zetian Mi
      Abstract: To date, there have been no efficient semiconductor light emitters operating in the green and amber wavelengths. This study reports on the synthesis of InGaN nanowire photonic crystals, including dot-in-nanowires, nanotriangles, and nanorectangles with precisely controlled size, spacing, and morphology, and further demonstrates that bottom-up InGaN photonic crystals can exhibit highly efficient and stable emission. The formation of stable and scalable band edge modes in defect-free InGaN nanowire photonic crystals is directly measured by cathodoluminescence studies. The luminescence emission, in terms of both the peak position (λ ≈ 505 nm) and spectral linewidths (full-width-half-maximum ≈ 12 nm), remains virtually invariant in the temperature range of 5–300 K and under excitation densities of 29 W cm−2 to 17.5 kW cm−2. To the best of our knowledge, this is the first demonstration of the absence of Varshni and quantum-confined Stark effects in wurtzite InGaN light emitters—factors that contribute significantly to the efficiency droop and device instability under high-power operation. Such distinct emission properties of InGaN photonic crystals stem directly from the strong Purcell effect, due to efficient coupling of the spontaneous emission to the highly stable and scalable band-edge modes of InGaN photonic crystals, and are ideally suited for uncooled, high-efficiency light-emitting-diode operation.The formation of stable and scalable band-edge modes in defect-free InGaN photonic crystals is directly measured for the first time. This is also the first demonstration of the absence of the quantum-confined Stark effect and Varshni effect in InGaN light emitters—factors that contribute significantly to efficiency droop and device instability under high-power operation.
      PubDate: 2017-08-04T00:56:02.106224-05:
      DOI: 10.1002/adfm.201702364
       
  • A Single Droplet-Printed Double-Side Universal Soft Electronic Platform
           for Highly Integrated Stretchable Hybrid Electronics
    • Authors: Junghwan Byun; Eunho Oh, Byeongmoon Lee, Sangwoo Kim, Seunghwan Lee, Yongtaek Hong
      Abstract: Soft features in electronic devices have provided an opportunity of gleaning a wide spectrum of intimate biosignals. Lack of data processing tools in a soft form, however, proclaims the need of bulky wires or low-performance near-field communication externally linked to a “rigid” processor board, thus tarnishing the true meaning of “soft” electronics. Furthermore, although of rising interest in stretchable hybrid electronics, lack of consideration in multilayer, miniaturized design and system-level data computing limits their practical use. The results presented here form the basis of fully printable, system-level soft electronics for practical data processing and computing with advanced capabilities of universal circuit design and multilayer device integration into a single platform. Single droplet printing-based integration of rigid islands and core–shell vertical interconnect access (via) into a common soft matrix with a symmetric arrangement leads to a double-side universal soft electronic platform that features site-selective, simultaneous double-side strain isolation, and vertical interconnection, respectively. Systematic studies of island-morphology engineering, surface-strain mapping, and electrical analysis of the platform propose optimized designs. Commensurate with the universal layout, a complete example of double-side integrated, stretchable 1 MHz binary decoders comprised of 36 logic gates interacting with 9 vias is demonstrated by printing-based, double-side electronic functionalization.Single droplet printing of functional ink with geometric optimization enables a double-side universal soft electronic platform that features site-selective, simultaneous double-side (top and bottom) strain-isolating with printed islands, and vertical-interconnecting with printed core–shell vias. Based on the printing-based, double-side electronic functionalization process, highly integrated stretchable hybrid electronics are demonstrated on the platform.
      PubDate: 2017-08-03T02:47:39.679479-05:
      DOI: 10.1002/adfm.201701912
       
  • Truly Electroforming-Free and Low-Energy Memristors with Preconditioned
           Conductive Tunneling Paths
    • Authors: Jung Ho Yoon; Jiaming Zhang, Xiaochen Ren, Zhongrui Wang, Huaqiang Wu, Zhiyong Li, Mark Barnell, Qing Wu, Lincoln J. Lauhon, Qiangfei Xia, J. Joshua Yang
      Abstract: 1S1R (1 selector and 1 memristor) is a laterally scalable and vertically stackable scheme that can lead to the ultimate memristor density for either memory or neural network applications. In such a scheme, the memristor device needs to be truly electroforming-free and operated at both low currents and low voltages in order to be compatible with a two-terminal selector. In this work, a new type of memristor with a preconditioned tunneling conductive path is developed to achieve the required performance characteristics, including truly electroforming-free, low current below 30 µA (potentially
      PubDate: 2017-08-03T00:51:32.50741-05:0
      DOI: 10.1002/adfm.201702010
       
  • Atomic-Scale CoOx Species in Metal–Organic Frameworks for Oxygen
           Evolution Reaction
    • Authors: Shuo Dou; Chung-Li Dong, Zhe Hu, Yu-Cheng Huang, Jeng-lung Chen, Li Tao, Dafeng Yan, Dawei Chen, Shaohua Shen, Shulei Chou, Shuangyin Wang
      Abstract: The activity of electrocatalysts strongly depends on the number of active sites, which can be increased by downsizing electrocatalysts. Single-atom catalysts have attracted special attention due to atomic-scale active sites. However, it is a huge challenge to obtain atomic-scale CoOx catalysts. The Co-based metal–organic frameworks (MOFs) own atomically dispersed Co ions, which motivates to design a possible pathway to partially on-site transform these Co ions to active atomic-scale CoOx species, while reserving the highly porous features of MOFs. In this work, for the first time, the targeted on-site formation of atomic-scale CoOx species is realized in ZIF-67 by O2 plasma. The abundant pores in ZIF-67 provide channels for O2 plasma to activate the Co ions in MOFs to on-site produce atomic-scale CoOx species, which act as the active sites to catalyze the oxygen evolution reaction with an even better activity than RuO2.Through the efficient and mild O2-plasma process, atomic-scale CoOx species in a ZIF-67 matrix are on-site formed, which are in favor of combining with OH* to act as active sites to directly catalyze the oxygen evolution reduction with an even better activity than commercial RuO2.
      PubDate: 2017-08-03T00:50:55.899477-05:
      DOI: 10.1002/adfm.201702546
       
  • Disordered Atomic Packing Structure of Metallic Glass: Toward Ultrafast
           Hydroxyl Radicals Production Rate and Strong Electron Transfer Ability in
           Catalytic Performance
    • Authors: Zhe Jia; Xiaoguang Duan, Peng Qin, Wenchang Zhang, Weimin Wang, Chao Yang, Hongqi Sun, Shaobin Wang, Lai-Chang Zhang
      Abstract: Developing new functional applications of metallic glasses in catalysis is an active and pivotal topic for materials science as well as novel environmental catalysis processes. Compared to the crystalline materials with highly ordered atomic packing, metallic glass has a simply disordered atomic structure. Recent reports have demonstrated that the metallic glasses are indeed having many superiorly catalytic properties, yet the understanding of the mechanism is insufficient. In this work, the structural relaxation (α-relaxation) by annealing in an amorphous Fe78Si9B13 alloy is studied for unraveling the catalytic mechanism at the atomic scale. The volume fractions of the crystalline structures, such as α-Fe, Fe2Si, and Fe2B, in the as-received and annealed metallic glasses are fully characterized. It is found that the randomly atomic packing structure with weak atomic bonding in the as-received metallic glass has an efficient electron transfer capability, presenting advanced superiorities in the aspects of production rate of hydroxyl radicals (•OH), dye degradation rate (k), and essential degradation ability (KSA) for water treatment. The discovery of this critically important work unveils why using metallic glasses as catalysts has higher reactivity than the crystalline materials, and more importantly, it provides new research opportunities into the study of synthetic catalysts.Compared to highly ordered atomic packing structure of their crystalline counterparts, the excellent catalytic performance of metallic glasses originates from their randomly atomic packing structure, presenting a better electron transfer capability, advanced superiorities in the aspects of production rate of hydroxyl radicals (•OH), dye degradation rate (k), and essential degradation ability (KSA) for water treatment.
      PubDate: 2017-08-02T12:16:04.084863-05:
      DOI: 10.1002/adfm.201702258
       
  • Polarization-Sensitive Single-Wall Carbon Nanotubes All-in-One
           Photodetecting and Emitting Device Working at 1.55 µm
    • Authors: Matteo Balestrieri; Al-Saleh Keita, Elena Duran-Valdeiglesias, Carlos Alonso-Ramos, Weiwei Zhang, Xavier Le Roux, Eric Cassan, Laurent Vivien, Viktor Bezugly, Artem Fediai, Vincent Derycke, Arianna Filoramo
      Abstract: Functional and easy-to-integrate nanodevices operating in the telecom wavelength ranges are highly desirable. Indeed, the pursuit for faster, cheaper, and smaller transceivers for datacom applications is fueling the interest in alternative materials to develop the next generation of photonic devices. In this context, single wall carbon nanotubes (SWNTs) have demonstrated outstanding electrical and optical properties that make them an ideal material for the realization of ultracompact optoelectronic devices. Still, the mixture in chirality of as-synthesized SWNTs and the necessity of precise positioning of SWNT-based devices hinder the development of practical devices. Here, the realization of operational devices obtained using liquid solution-based techniques is reported, which allow high-purity sorting and localized deposition of aligned semiconducting SWNTs (s-SWNTs). More specifically, devices are demonstrated by combining a polymer assisted extraction method, which enables a very effective selection of s-SWNTs with a diameter of about 1–1.2 nm, with dielectrophoresis, which localizes the deposition onto silicon wafers in aligned arrays in-between prepatterned electrodes. Thus, long semiconducting nanotubes directly contact the electrodes and, when asymmetric contacts (i.e., source and drain made of different metals) are used, each device can operate both as photoemitter and as photodetector in the telecom band around 1.55 µm in air at room temperature.Functional and easy-to-integrate nanodevices operating in the telecom wavelength ranges are highly desirable. Here, such devices are demonstrated by combining an effective selection of semiconducting single wall carbon nanotube with their deposition in arrays using dielectrophoresis. Specifically the obtained device performs, both as photoemitter and as photodetector, around 1.55 µm in air at room temperature.
      PubDate: 2017-08-02T12:15:32.487078-05:
      DOI: 10.1002/adfm.201702341
       
  • Two-Dimensional Nanostructured Materials for Gas Sensing
    • Authors: Xianghong Liu; Tiantian Ma, Nicola Pinna, Jun Zhang
      Abstract: Two-dimensional (2D) nanostructures are highly attractive for fabricating nanodevices due to their high surface-to-volume ratio and good compatibility with device design. In recent years 2D nanostructures of various materials including metal oxides, graphene, metal dichalcogenides, phosphorene, BN and MXenes, have demonstrated significant potential for gas sensors. This review aims to provide the most recent advancements in utilization of various 2D nanomaterials for gas sensing. The common methods for the preparation of 2D nanostructures are briefly summarized first. The focus is then placed on the sensing performances provided by devices integrating 2D nanostructures. Strategies for optimizing the sensing features are also discussed. By combining both the experimental results and the theoretical studies available, structure-properties correlations are discussed. The conclusion gives some perspectives on the open challenges and future prospects for engineering advanced 2D nanostructures for high-performance gas sensors devices.Two-dimensional (2D) nanostructures are highly attractive for nanodevices due to their high surface-to-volume ratio and good compatibility with device design. The most recent advancements in the synthesis, surface engineering, and funcationlization of various 2D nanostructures including metal oxides, graphene, metal dichalcogenides, phosphorene, BN and Mxenes for high-performance gas sensors are reviewed.
      PubDate: 2017-08-02T12:15:18.377847-05:
      DOI: 10.1002/adfm.201702168
       
  • Bandgap Engineering in OH-Functionalized Silicon Nanocrystals: Interplay
           between Surface Functionalization and Quantum Confinement
    • Authors: Marius Bürkle; Mickaël Lozac'h, Calum McDonald, Davide Mariotti, Koji Matsubara, Vladimir Švrček
      Abstract: In this work, a systematic first-principles study of the quasi-band structure of silicon nanocrystals (Si-NCs) is provided, focusing on bandgap engineering by combining quantum confinement of the electronic states with OH surface-functionalization. A mapping between the bandgap, Si-NC diameter, and the degree of hydroxide coverage is provided, which can be used as a guideline for bandgap engineering. Complementary to first-principles calculations, the photoluminescence (PL) wavelength of Si-NCs in the quantum-confinement regime is measured with well-defined diameters between 1 and 4 nm. The Si-NCs are prepared by means of a microplasma technique, which allows a surfactant-free engineering of the Si-NCs surface with OH groups. The microplasma treatment technique allows us to gradually change the degree of OH coverage, enabling us, in turn, to gradually shift the emitted light in the PL spectra by up to 100 nm to longer wavelengths. The first-principles calculations are consistent with the experimentally observed dependence of the wavelengths on the OH coverage and show that the PL redshift is determined by the charge transfer between the Si-NC and the functional groups, while on the other hand surface strain plays only a minor part.A systematic way to engineer the bandgap of silicon nanocrystals by means of variable particle-size and surface chemistry is introduced, where the surface chemistry is tailored by replacing H with OH. This is a simple yet powerful approach allowing to gradually tune the bandgap and to control optical properties, e.g., for applications in third-generation solar cells.
      PubDate: 2017-08-02T12:13:45.347893-05:
      DOI: 10.1002/adfm.201701898
       
  • Nanogap-Rich Au Nanowire SERS Sensor for Ultrasensitive Telomerase
           Activity Detection: Application to Gastric and Breast Cancer Tissues
           Diagnosis
    • Authors: Gayoung Eom; Hongki Kim, Ahreum Hwang, Hye-Young Son, Yuna Choi, Jeong Moon, Donghyeong Kim, Miyeon Lee, Eun-Kyung Lim, Jinyoung Jeong, Yong-Min Huh, Min-Kyo Seo, Taejoon Kang, Bongsoo Kim
      Abstract: Telomerase has attracted much attention as a universal cancer biomarker because telomerase is overexpressed in more than 85% of human cancer cells while suppressed in normal somatic cells. Since a strong association exists between telomerase activity and human cancers, the development of effective telomerase activity assay is critically important. Here, a nanogap-rich Au nanowire (NW) surface-enhanced Raman scattering (SERS) sensor is reported for detection of telomerase activity in various cancer cells and tissues. The nanogap-rich Au NWs are constructed by deposition of nanoparticles on single-crystalline Au NWs and provided highly reproducible SERS spectra. The telomeric substrate (TS) primer-attached nanogap-rich Au NWs can detect telomerase activity through SERS measurement after the elongation of TS primers, folding into G-quadruplex structures, and intercalation of methylene blue. This sensor enables us to detect telomerase activity from various cancer cell lines with a detection limit of 0.2 cancer cells mL−1. Importantly, the nanogap-rich Au NW sensor can diagnose gastric and breast cancer tissues accurately. The nanogap-rich Au NW sensors show strong SERS signals only in the presence of tumor tissues excised from 16 tumor-bearing mice, while negligible signals in the presence of heated tumor tissues or normal tissues. It is anticipated that nanogap-rich Au NW SERS sensors can be used for a universal cancer diagnosis and further biomedical applications including a diverse biomarker sensing.A nanogap-rich Au nanowire (NW) surface-enhanced Raman scattering (SERS) sensor is developed for ultrasensitive and specific detection of telomerase activity. The optimized nanogap-rich Au NW can provide highly reproducible and strong SERS signals. Using nanogap-rich Au NW SERS sensors, telomerase activities of cancer cells and tumor tissues are successfully detected, suggesting the potential applicability of nanogap-rich Au NW SERS sensor in cancer diagnosis.
      PubDate: 2017-08-02T12:13:25.348838-05:
      DOI: 10.1002/adfm.201701832
       
  • In Situ Electrochemical Activation of Atomic Layer Deposition Coated MoS2
           Basal Planes for Efficient Hydrogen Evolution Reaction
    • Authors: Youngmin Kim; David H. K. Jackson, Daewon Lee, Min Choi, Tae-Wan Kim, Soon-Yong Jeong, Ho-Jeong Chae, Hyun Woo Kim, Noejung Park, Hyunju Chang, Thomas F. Kuech, Hyung Ju Kim
      Abstract: Molybdenum disulfide (MoS2), which is composed of active edge sites and a catalytically inert basal plane, is a promising catalyst to replace the state-of-the-art Pt for electrochemically catalyzing hydrogen evolution reaction (HER). Because the basal plane consists of the majority of the MoS2 bulk materials, activation of basal plane sites is an important challenge to further enhance HER performance. Here, an in situ electrochemical activation process of the MoS2 basal planes by using the atomic layer deposition (ALD) technique to improve the HER performance of commercial bulk MoS2 is first demonstrated. The ALD technique is used to form islands of titanium dioxide (TiO2) on the surface of the MoS2 basal plane. The coated TiO2 on the MoS2 surface (ALD(TiO2)-MoS2) is then leached out using an in situ electrochemical activation method, producing highly localized surface distortions on the MoS2 basal plane. The MoS2 catalysts with activated basal plane surfaces (ALD(Act.)-MoS2) have dramatically enhanced HER kinetics, resulting from more favorable hydrogen-binding.The catalytically inert basal plane of MoS2 is activated for the hydrogen evolution reaction (HER) by combining the atomic layer deposition (ALD) technique and an in situ electrochemical activation process. The basal plane activated MoS2 (ALD(Act.)-MoS2) catalysts significantly improve the HER performance, resulting from more favorable hydrogen-binding.
      PubDate: 2017-08-02T12:13:03.349396-05:
      DOI: 10.1002/adfm.201701825
       
  • Self-Healing Silk Fibroin-Based Hydrogel for Bone Regeneration: Dynamic
           Metal-Ligand Self-Assembly Approach
    • Authors: Liyang Shi; Fanlu Wang, Wei Zhu, Zongpu Xu, Sabine Fuchs, Jöns Hilborn, Liangjun Zhu, Qi Ma, Yingjie Wang, Xisheng Weng, Dmitri A. Ossipov
      Abstract: Despite advances in the development of silk fibroin (SF)-based hydrogels, current methods for SF gelation show significant limitations such as lack of reversible crosslinking, use of nonphysiological conditions, and difficulties in controlling gelation time. In the present study, a strategy based on dynamic metal-ligand coordination chemistry is developed to assemble SF-based hydrogel under physiological conditions between SF microfibers (mSF) and a polysaccharide binder. The presented SF-based hydrogel exhibits shear-thinning and autonomous self-healing properties, thereby enabling the filling of irregularly shaped tissue defects without gel fragmentation. A biomineralization approach is used to generate calcium phosphate-coated mSF, which is chelated by bisphosphonate ligands of the binder to form reversible crosslinkages. Robust dually crosslinked (DC) hydrogel is obtained through photopolymerization of acrylamide groups of the binder. DC SF-based hydrogel supports stem cell proliferation in vitro and accelerates bone regeneration in cranial critical size defects without any additional morphogenes delivered. The developed self-healing and photopolymerizable SF-based hydrogel possesses significant potential for bone regeneration application with the advantages of injectability and fit-to-shape molding.Reversible coordination bonds are employed to achieve self-assembly of novel silk fibroin hydrogel that flows on applied stress, rapidly self-heal after injection, and is subsequently photopolymerized. Using silk microfibers as templates for biomineralization and a natural biopolymer binder provides hierarchical structure of the network. Implantation of the hydrogel into rat cranial critical size defect facilitates bone regeneration without exogenous growth factors.
      PubDate: 2017-08-02T12:12:39.840929-05:
      DOI: 10.1002/adfm.201700591
       
  • Nanostructured Materials for Neural Electrical Interfaces
    • Authors: Jessamyn A. Fairfield
      Abstract: Neural electrical interfaces that accurately detect signals from active neurons with minimal signal loss or biological damage are critical to advancing our understanding of neurophysiology and neural coding. Significant physics and engineering issues exist in creating low-impedance interfaces that can efficiently and reliably inject charge from tissue to sensor, as well as biological issues in minimizing immune response, unwanted chemical reactions, and cell damage. The incorporation of nanostructured materials in neural electrodes provides a structural solution by matching the feature size and mechanical properties of neural tissue while improving electrical contact and charge transfer parameters. Indeed, nature contains many examples of nanoscale and layered structures, suggesting engineering approaches that can be mimicked to better interface with the brain. The potential toxicity of nanoscale objects can be controlled by selecting appropriate materials, and the nanomaterials can either be used as coatings for traditional neural electrodes or as electrode materials themselves, for incorporation into electrode arrays with multiplexed readouts as brain–machine interfaces. This review provides an overview of the scientific challenges in neural electrodes, and explores recent advances and future directions in the application of metallic, semiconducting, carbon-based, and polymer nanomaterials to electrodes designed to interface with the brain.Nanostructured materials are uniquely capable of addressing persistent challenges in state-of-the-art neural electrical interfaces. This review explores how nanomaterials based on metals, semiconductors, carbon, and polymers are ideal for creating low-impedance, low-noise, biocompatible electrodes for sensing and control of neural function.
      PubDate: 2017-08-02T12:12:00.593023-05:
      DOI: 10.1002/adfm.201701145
       
  • Neutron Reflectivity and Performance of Polyamide Nanofilms for Water
           Desalination
    • Authors: Fabrizia Foglia; Santanu Karan, Manuela Nania, Zhiwei Jiang, Alexandra E. Porter, Robert Barker, Andrew G. Livingston, João T. Cabral
      Abstract: The structure and hydration of polyamide (PA) membranes are investigated with a combination of neutron and X-ray reflectivity, and their performance is benchmarked in reverse osmosis water desalination. PA membranes are synthesized by the interfacial polymerization of m-phenylenediamine (MPD) and trimesoyl chloride (TMC), varying systematically reaction time, concentration, and stoichiometry, to yield large-area exceptionally planar films of ≈10 nm thickness. Reflectivity is employed to precisely determine membrane thickness and roughness, as well as the (TMC/MPD) concentration profile, and response to hydration in the vapor phase. PA film thickness is found to increase linearly with reaction time, albeit with a nonzero intercept, and the composition cross-sectional profile is found to be uniform, at the conditions investigated. Vapor hydration with H2O and D2O from 0 to 100% relative humidity results in considerable swelling (up to 20%), but also yields uniform cross-sectional profiles. The resulting film thickness is found to be predominantly set by the MPD concentration, while TMC regulates water uptake. A favorable correlation is found between higher swelling and water uptake with permeance. The data provide quantitative insight into the film formation mechanisms and correlate reaction conditions, cross-sectional nanostructure, and performance of the PA active layer in RO membranes for desalination.The effect of reaction time, stoichiometry, and hydration on planar, nanofilm trimesoyl chloride (TMC)/m-phenylenediamine (MPD) model reverse osmosis membranes is quantified by neutron and X-ray reflectivity and correlated to membrane performance in water desalination. Film thickness increases linearly with reaction time, albeit with a nonzero intercept, and is predominantly set by the MPD concentration, while TMC regulates water uptake.
      PubDate: 2017-08-02T12:10:39.870705-05:
      DOI: 10.1002/adfm.201701738
       
  • Controlled Synthesis of Ultrathin 2D β-In2S3 with Broadband Photoresponse
           by Chemical Vapor Deposition
    • Authors: Wenjuan Huang; Lin Gan, Haotian Yang, Nan Zhou, Renyan Wang, Wanhui Wu, Huiqiao Li, Ying Ma, Haibo Zeng, Tianyou Zhai
      Abstract: β-In2S3 is a natural defective III–VI semiconductor attracting considerable interests but lack of efficient method for its 2D form fabrication. Here, for the first time, this paper reports controlled synthesis of ultrathin 2D β-In2S3 flakes via a facile space-confined chemical vapor deposition method. The natural defects in β-In2S3 crystals, clearly revealed by optical spectra and optoelectronic measurement, strongly modulate the (opto)-electronic of as-fabricated β-In2S3 and render it a broad detection range from visible to near-infrared. Particularly, the as-fabricated β-In2S3 photodetector shows a high photoresponsivity of 137 A W−1, a high external quantum efficiency of 3.78 × 104%, and a detectivity of 4.74 × 1010 Jones, accompanied with a fast rise and decay time of 6 and 8 ms, respectively. In addition, an interesting linear response to the testing power intensities range is observed, which can also be understood by the presence of natural defects. The unique defective structure and intrinsic optical properties of β-In2S3, together with its controllable growth, endow it with great potential for future applications in electronics and optoelectronics.High-quality ultrathin 2D β-In2S3 flakes are synthesized for the first time by space-confined chemical vapor deposition. The native intrinsic defects in β-In2S3 crystals strongly enhance the performance of the as-fabricated β-In2S3 photodetector toward broad range detection from visible to near-infrared light. This study will pave the way for large-scale application of In2S3 in optoelectronic fields.
      PubDate: 2017-08-01T09:34:55.269022-05:
      DOI: 10.1002/adfm.201702448
       
  • Role of Ordered Ni Atoms in Li Layers for Li-Rich Layered Cathode
           Materials
    • Authors: Moon Young Yang; Sangryun Kim, Kyungsu Kim, Woosuk Cho, Jang Wook Choi, Yoon Sung Nam
      Abstract: Li-rich layered oxide materials are promising candidates for high-energy Li-ion batteries. They show high capacities of over 200 mAh g−1 with the additional occupation of Li in their transition metal layers; however, the poor cycle performance induced by an irreversible phase transition limits their use in practical applications. In recent work, an atomic-scale modified surface, in which Ni is ordered at 2c sites in the Li layers, significantly improves the performance in terms of reversible capacity and cycling stability. The role of the incorporated Ni on this performance, however, is not yet clearly understood. Here, the effects of the ordered Ni on Li battery performance are presented, based on first-principles calculations and experimental observations. The Ni substitution suppresses the oxygen loss by moderating the oxidation of oxygen ions during the delithiation process and forms bonds with adjacent oxygen after the first deintercalation of Li ions. These NiO bonds contribute to the formation of a solid surface, resulting in the improved cycling stability. Moreover, the multivalent Ni suppresses Mn migration to the Li-sites that causes the undesired phase transition. These findings from theoretical calculations and experimental observations provide insights to enhance the electrochemical performance of Li-rich layered oxides.The regularly ordered Ni substitution in the Li-rich layered oxide significantly improves the battery performance in terms of reversible capacity and cycling stability. The combinatorial study using first-principles calculations and experiments reveals that Ni substitution effectively suppresses the oxygen loss and cation mixing that induces the undesired phase transition for the Li-rich layered cathode materials.
      PubDate: 2017-08-01T09:16:46.563483-05:
      DOI: 10.1002/adfm.201700982
       
  • Conjugated Small Molecule for Efficient Hole Transport in High-Performance
           p-i-n Type Perovskite Solar Cells
    • Authors: Liyan Yang; Feilong Cai, Yu Yan, Jinghai Li, Dan Liu, Andrew J. Pearson, Tao Wang
      Abstract: The π-conjugated organic small molecule 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl) benzenamine] (TAPC) has been explored as an efficient hole transport material to replace poly(3,4-ethylenedio-xythiophene):poly(styrenesulfonate) (PEDOT:PSS) in the preparation of p-i-n type CH3NH3PbI3 perovskite solar cells. Smooth, uniform, and hydrophobic TAPC hole transport layers can be facilely deposited through solution casting without the need for any dopants. The power conversion efficiency of perovskite solar cells shows very weak TAPC layer thickness dependence across the range from 5 to 90 nm. Thermal annealing enables improved hole conductivity and efficient charge transport through an increase in TAPC crystallinity. The perovskite photoactive layer cast onto thermally annealed TAPC displays large grains and low residual PbI2, leading to a high charge recombination resistance. After optimization, a stabilized power conversion efficiency of 18.80% is achieved with marginal hysteresis, much higher than the value of 12.90% achieved using PEDOT:PSS. The TAPC-based devices also demonstrate superior stability compared with the PEDOT:PSS-based devices when stored in ambient circumstances, with a relatively high humidity ranging from 50 to 85%.Conjugated molecule 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl) benzenamine] (TAPC) has been explored to replace poly(3,4-ethylenedio-xythiophene):poly(styrenesulfonate) in perovskite solar cells. The CH3NH3PbI3 solar cells are hysteresis-free, with marginal dependence on the thickness of TAPC, and achieve a power conversion efficiency of 18.8 over 12.9% as a result of increased Jsc, Voc, and fill factor.
      PubDate: 2017-07-17T07:15:46.26835-05:0
      DOI: 10.1002/adfm.201702613
       
  • Energy Saving Electrochromic Polymer Windows with a Highly Transparent
           Charge-Balancing Layer
    • Authors: Younghoon Kim; Haijin Shin, Minsu Han, Seogjae Seo, Woojae Lee, Jongbeom Na, Chihyun Park, Eunkyoung Kim
      Abstract: Highly transparent TiO2 nanoparticles are explored as a non-electrochromic (non-EC) charge-balancing layer for a high color contrast, bistable electrochromic window (ECW). The TiO2 nanoparticle (TNP) layer increases the potential at the EC polymer electrode, thereby lowering the working voltage of the ECW. This leads to lower the power consumption of ECWs without loss in the high color contrast (ΔT> 72%) and to remarkably improve the cyclability (ΔT change
      PubDate: 2017-07-14T00:32:23.582688-05:
      DOI: 10.1002/adfm.201701192
       
  • Novel Core–Shell FeOF/Ni(OH)2 Hierarchical Nanostructure for
           All-Solid-State Flexible Supercapacitors with Enhanced Performance
    • Authors: Mengqiao Wang; Zhaoqiang Li, Chengxiang Wang, Ruizheng Zhao, Caixia Li, Dexiang Guo, Luyuan Zhang, Longwei Yin
      Abstract: Well-controlled core–shell hierarchical nanostructures based on oxyfluoride and hydroxide are for the first time rationally designed and synthesized via a simple solvothermal and chemical precipitation route, in which FeOF nanorod acts as core and porous Ni(OH)2 nanosheets as shell. When evaluated as electrodes for supercapacitors, a high specific capacitance of 1452 F g−1 can be obtained at a current density of 1 A g−1. Even as the current density increases to 10 A g−1, the core–shell hybrid still reserves a noticeable capacitance of 1060 F g−1, showing an excellent rate capacity. Furthermore, all-solid-state flexible asymmetric supercapacitor based on the FeOF/Ni(OH)2 hybrid as a positive electrode and activated carbon as a negative electrode shows high power density, high energy density, and long cycling lifespan. The excellent electrochemical performance of the FeOF/Ni(OH)2 core–shell hybrid is ascribed to the unique microstructure and synergistic effects. FeOF nanorod from FeF3 by partial substitution of fluorine with oxygen behaves as a low intrinsic resistance, thus facilitating charge transfer processes. While the hierarchical Ni(OH)2 nanosheets with large surface area provide enough active sites for redox chemical reactions, leading to greatly enhanced electrochemical activity. The well-controllable oxyfluoride/hydroxide hybrid is inspiring, opening up a new way to design new electrodes for next-generation all-solid-state supercapacitors.Well-controlled core–shell hierarchical FeOF/Ni(OH)2 hybrids based on oxyfluoride and hydroxide are rationally designed via a simple route. FeOF nanorod facilitates the charge transfer process; hierarchical Ni(OH)2 nanosheets with large surface area provide enough active sites for redox chemical reactions. All-solid-state flexible asymmetric supercapacitor based on FeOF/Ni(OH)2 hybrid and activated-carbon shows high power density, high energy density, and long cycling lifespan.
      PubDate: 2017-07-14T00:26:11.998883-05:
      DOI: 10.1002/adfm.201701014
       
  • Assembly and Characterizations of Bifunctional Fluorescent and Magnetic
           Microneedles With One Decade Length Tunability
    • Authors: Jean-Baptiste Lugagne; Gwennhaël Brackx, Emek Seyrek, Sophie Nowak, Yann Sivry, Leticia Vitorazi, Jean-François Berret, Pascal Hersen, Gaëlle Charron
      Abstract: This report presents the fabrication of bifunctional magnetic and fluorescent microneedles (µNDs) made of a ternary mixture of magnetic nanoparticles (NPs), quantum dots (QDs), and polyelectrolyte. The assembly relies on the electrostatic complexation of negatively charged NPs with positively charged polymer strands and is controlled by the charge ratio between the nanoparticle building blocks and the polymer mortar. The resulting 1D objects can be actuated using an external magnetic field and can be imaged using fluorescence microscopy, thanks to the fluorescent and superparamagnetic properties inherited from their NP constituents. Using a combination of core and surface characterizations and a state-of-the-art image analysis algorithm, the dependence of the brightness and length on the ternary composition is thoroughly investigated. In particular, statistics on hundreds of µNDs with a range of compositions show that the µNDs have a log-lormal length distribution and that their mean length can be robustly tuned in the 5–50 µm range to match the relevant length scales of various applications in micromixing, bioassays or biomechanics.Bifunctional microneedles are assembled from magnetic nanoparticles, quantum dots, and polyelectrolyte using a straightforward protocol. The microneedles are both fluorescent and responsive under an external magnetic field and their mean length can be tuned from 5 to 50 µm by playing on the starting composition to match the needs of several applications.
      PubDate: 2017-07-10T13:15:10.492856-05:
      DOI: 10.1002/adfm.201700362
       
  • Wide Field Magnetic Luminescence Imaging
    • Authors: Matthew P. P. Hodges; Martin Grell, Nicola A. Morley, Dan A. Allwood
      Abstract: This study demonstrates how magnetic-field-dependent luminescence from organic films can be used to image the magnetic configuration of an underlying sample. The organic semiconductors tetracene and rubrene exhibit singlet exciton fission, which is a process sensitive to magnetic fields. Here, thin films of these materials were characterized using photoluminescence spectrometry, atomic force microscopy, and photoluminescence magnetometry. The luminescence from these substrate-bound thin films is imaged to reveal the magnetic configuration of underlying Nd-Fe-B magnets. The tendency of rubrene to form amorphous films and produce large changes in photoluminescence under an applied magnetic field makes it more appropriate for magnetic field imaging than tetracene. This demonstration can be extended in the future to allow simple microscopic imaging of magnetic structure.A magnetic imaging technique is demonstrated that uses tetracene and rubrene thin films to probe the magnetic stray fields of macroscopic permanent magnets via steady-state photoluminescence at room temperature. This technique exploits singlet exciton fission to produce quantitative images. This proof of concept has the potential to be extended in the future to allow simple microscopic magnetic imaging.
      PubDate: 2017-07-06T07:12:50.971125-05:
      DOI: 10.1002/adfm.201606613
       
  • Gold Nanoparticles and g-C3N4-Intercalated Graphene Oxide Membrane for
           Recyclable Surface Enhanced Raman Scattering
    • Authors: Lulu Qu; Na Wang, Hui Xu, Weipeng Wang, Yang Liu, Lidia Kuo, T. P. Yadav, Jingjie Wu, Jarin Joyner, Yanhua Song, Haitao Li, Jun Lou, Robert Vajtai, Pulickel M. Ajayan
      Abstract: Toxic organic pollutants in the aquatic environment cause severe threats to both humans and the global environment. Thus, the development of robust strategies for detection and removal of these organic pollutants is essential. For this purpose, a multifunctional and recyclable membrane by intercalating gold nanoparticles and graphitic carbon nitride into graphene oxide (GNPs/g-C3N4/GO) is fabricated. The membranes exhibit not only superior surface enhanced Raman scattering (SERS) activity attributed to high preconcentration ability to analytes through π–π and electrostatic interactions, but also excellent catalytic activity due to the enhanced electron–hole separation efficiency. These outstanding properties allow the membrane to be used for highly sensitive detection of rhodamine 6G with a limit of detection of 5.0 × 10−14m and self-cleaning by photocatalytic degradation of the adsorbed analytes into inorganic small molecules, thus achieving recyclable SERS application. Furthermore, the excellent SERS activity of the membrane is demonstrated by detection of 4-chlorophenol at less than nanomolar level and no significant SERS or catalytic activity loss was observed when reusability is tested. These results suggest that the GNPs/g-C3N4/GO membrane provides a new strategy for eliminating traditional, single-use SERS substrates, and expands practical SERS application to simultaneous detection and removal of environmental pollutants.A multifunctional membrane including superior surface enhanced Raman scattering (SERS) and photocatalytic activity by intercalating gold nanoparticles and graphic carbon nitride into graphene oxide nanosheets is developed. The membrane exhibits the extraordinary ability for use in removal, SERS detection, and degradation of organic pollutants, holding great promise for environmental pollutants removal and monitoring.
      PubDate: 2017-07-03T07:22:12.021598-05:
      DOI: 10.1002/adfm.201701714
       
  • Synergistic Effect of Si Doping and Heat Treatments Enhances the
           Photoelectrochemical Water Oxidation Performance of TiO2 Nanorod Arrays
    • Authors: Changlong Chen; Yuling Wei, Guangzheng Yuan, Qinglong Liu, Ranran Lu, Xing Huang, Yi Cao, Peihua Zhu
      Abstract: TiO2 is a very promising photocatalytic material due to its merits including low cost, nontoxicity, high chemical stability, and photocorrosion resistance. However, it is also known that TiO2 is a wide bandgap material, and it is still challenging to achieve high photocatalytic performance driven by solar light. In this paper, silicon-doped TiO2 nanorod arrays are vertically grown on fluorine-doped tin oxide substrates and then are heat treated both in air and in vacuum. It is found that the silicon doping together with the heat treatment brings synergic effect to TiO2 nanorod films by increasing the crystallinity, producing abundant oxygen vacancies, enhancing the hydrophilicity as well as improving the electronic properties. When used as photoanodes in photoelectrochemical water splitting, under the condition of AM 1.5G simulated solar irradiation and without using any cocatalysts, these nanorod films show photocurrent density as high as 0.83 mA cm−2 at a potential of 1.23 V versus reversible hydrogen electrode, which is much higher than that of the TiO2 nanorod films without doping or heat treating. The silicon-doped TiO2 nanorod array films described in this paper are envisioned to provide valuable platforms for supporting catalysts and cocatalysts for efficient solar-light-assisted water oxidation and other solar-light-driven photocatalytic applications.TiO2 nanorod arrays subjected to Si doping and heat treatments achieve much-improved electronic properties due to the improvement of the crystallinity and the increase of the donor density, which are envisioned to provide valuable platforms for supporting catalysts and cocatalysts for efficient solar-light-assisted water oxidation and other solar-light-driven photocatalytic applications.
      PubDate: 2017-07-03T07:16:10.47211-05:0
      DOI: 10.1002/adfm.201701575
       
  • Robust Red Organic Nanoparticles for In Vivo Fluorescence Imaging of
           Cancer Cell Progression in Xenografted Zebrafish
    • Authors: Gengwei Lin; Purnima Naresh Manghnani, Duo Mao, Cathleen Teh, Yinghao Li, Zujin Zhao, Bin Liu, Ben Zhong Tang
      Abstract: Bright and red-emissive organic nanoparticles (NPs) are demonstrated as promising for in vivo fluorescence imaging. However, most red organic dyes show greatly weakened or quenched emission in the aggregated state. In this work, a robust red fluorophore (t-BPITBT-TPE) with strong aggregate-state photoluminescence and good biocompatibility is presented. The NPs comprised of t-BPITBT-TPE aggregates encapsulated within 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol) (DSPE-mPEG) micelles exhibit a photoluminescence peak at 660 nm with a high fluorescence quantum yield of 32% in aqueous media. The NPs can be facilely charged by using the same polymeric matrix with different terminal groups, e.g., methoxy (DSPE-mPEG), amine (DSPE-PEG-NH2), or carboxymethyl (DSPE-PEG-COOH) groups. The biocompatibility, toxicity, circulation, and biodistribution of the NPs are assessed using the zebrafish model through whole embryo soaking and intravenous delivery. Furthermore, HeLa and MCF-7 cells tagged with t-BPITBT-TPE in DSPE-PEG-NH2-TAT polymer NPs are xenografted into zebrafish larvae to successfully track the cancer cell proliferation and metastasis, demonstrating that these new NPs are efficient cancer cell trackers. In addition, the NPs also show good in vivo imaging ability toward 4T1 tumors in xenografted BALB/c mice.Bright red organic nanoparticles are prepared for the study of their toxicity, circulation, and biodistribution in zebrafish. Different cancer cells tagged with these nanoparticles are xenografted into zebrafish larvae, realizing long-term tracing of their proliferation and metastasis in zebrafish.
      PubDate: 2017-07-03T01:41:38.594081-05:
      DOI: 10.1002/adfm.201701418
       
  • Large-Area, Flexible Broadband Photodetector Based on ZnS–MoS2
           Hybrid on Paper Substrate
    • Authors: P. Thanga Gomathi; Parikshit Sahatiya, Sushmee Badhulika
      Abstract: Flexible broadband photodetectors based on 2D MoS2 have gained significant attention due to their superior light absorption and increased light sensitivity. However, pristine MoS2 has absorption only in visible and near IR spectrum. This paper reports a paper-based broadband photodetector having ZnS–MoS2 hybrids as active sensing material fabricated using a simple, cost effective two-step hydrothermal method wherein trilayer MoS2 is grown on cellulose paper followed by the growth of ZnS on MoS2. Optimization in terms of process parameters is done to yield uniform trilayer MoS2 on cellulose paper. UV sensing property of ZnS and broadband absorption of MoS2 in visible and IR, broadens the range from UV to near IR. ZnS plays the dual role for absorption in UV and in the generation of local electric fields, thereby increasing the sensitivity of the sensor. The fabricated photodetector exhibits a higher responsivity toward the visible light when compared to UV and IR light. Detailed studies in terms of energy band diagram are presented to understand the charge transport mechanism. This represents the first demonstration of a paper-based flexible broadband photodetector with excellent photoresponsivity and high bending capability that can be used for wearable electronics, flexible security, and surveillance systems, etc.Herein, a paper-based broadband photodetector applying ZnS–MoS2 (trilayer) hybrids as active sensing material is reported for the first time. A simple hydrothermal process is used for fabrication. UV sensing property of ZnS and broadband absorption of MoS2 in visible and IR, broadens the range from UV to near- IR with higher sensitivity toward visible light.
      PubDate: 2017-07-03T01:40:47.791432-05:
      DOI: 10.1002/adfm.201701611
       
  • Reversible Thermal Tuning of All-Dielectric Metasurfaces
    • Authors: Mohsen Rahmani; Lei Xu, Andrey E. Miroshnichenko, Andrei Komar, Rocio Camacho-Morales, Haitao Chen, Yair Zárate, Sergey Kruk, Guoquan Zhang, Dragomir N. Neshev, Yuri S. Kivshar
      Abstract: All-dielectric metasurfaces provide a powerful platform for a new generation of flat optical devices, in particular, for applications in telecommunication systems, due to their low losses and high transparency in the infrared. However, active and reversible tuning of such metasurfaces remains a challenge. This study experimentally demonstrates and theoretically justifies a novel scenario of the dynamical reversible tuning of all-dielectric metasurfaces based on the temperature-dependent change of the refractive index of silicon. How to design an all-dielectric metasurface with sharp resonances by achieving interference between magnetic dipole and electric quadrupole modes of constituted nanoparticles arranged in a 2D lattice is shown. Thermal tuning of these resonances can cause drastic but reciprocal changes in the directional scattering of the metasurface in a spectral window of 75 nm. This change can result in a 50-fold enhancement of the radiation directionality. This type of reversible tuning can play a significant role in novel flat optical devices including the metalenses and metaholograms.Via controlling the temperature and employing the right combination of the electric and magnetic resonant responses of the metasurfaces, drastic and reciprocal interchanges in directional scattering are demonstrated experimentally and theoretically. At 1425 nm forward to backward ratio variation from 1 to>50 can be obtained. The results provide an important step toward tunable nanophotonic components and all-optical circuitry on a chip.
      PubDate: 2017-07-03T01:21:23.154565-05:
      DOI: 10.1002/adfm.201700580
       
  • Fully-Inkjet-Printed Ag-Coil/NiZn-Ferrite for Flexible Wireless Power
           Transfer Module: Rigid Sintered Ceramic Body into Flexible Form
    • Authors: Murali Bissannagari; Woosung Lee, Woong Yong Lee, Jun Hwan Jeong, Jihoon Kim
      Abstract: Despite the material performances being superior to those of organic materials, inorganic materials are typically excluded for use in flexible and deformable electronic systems because of their rigid nature and the requirement for high processing temperature. This work presents a novel method of utilizing rigid NiZn-ferrite films in a flexible platform and offers an opportunity to realize a flexible wireless power transfer (WPT) module. Inkjet printing is introduced in this study since it can coat NiZn-ferrite films as well as pattern inductor coils for WPTs. A thermochemically inert buffer layer is selected based on a thermodynamic analysis and is introduced as a buffer layer for the NiZn-ferrite to prevent chemical reaction between the ferrite film and the substrate and ensure that the ferrite film can be easily separated from the substrate during a high-temperature sintering process. A Ag-inductor coil is printed on the NiZn-ferrite layer, and then the entire layer is embedded into polydimethylsiloxane, which renders the WPT module flexible. The flexibility of the WPT module is characterized by a bending test, and the structural and magnetic properties are also investigated. The performance of the flexible WPT module is demonstrated by transmitting wireless power to a light emitting diode.A flexible wireless power transfer (WPT) module is prepared by embedding a Ag-inductor coil/NiZn-ferrite layer into polydimethylsiloxane. This work presents a creative method to utilize a rigid ferrite film in a flexible platform for future flexible electronics. The performance of the flexible WPT module is demonstrated by transmitting a wireless power to a light emitting diode.
      PubDate: 2017-06-26T01:13:25.685267-05:
      DOI: 10.1002/adfm.201701766
       
  • Solution Processed Boron Nitride Nanosheets: Synthesis, Assemblies and
           Emerging Applications
    • Authors: Wei Luo; Yanbin Wang, Emily Hitz, Yi Lin, Bao Yang, Liangbing Hu
      Abstract: In the last decade, few-layer boron nitride nanosheets and monolayer BN nanosheet (BNNS) have gained much attention due to their unique physical and chemical properties. To date, BNNS can be produced by micromechanical cleavage of BN crystal, unzipping BN nanotubes, chemical vapor deposition (CVD), and solution processed exfoliation from bulk BN powder. Due to the low cost and abundance of bulk BN powder and its simple processing for potentially scalable production, great efforts have been devoted toward solution processed exfoliation. In this feature article, recent significant advances in solution processed synthesis of BNNS are summarized. In particular, the solvent choice for one-step BN exfoliation is highlighted. Multi-dimensional assemblies consisting of BNNS are discussed, such as BN fiber, BN paper, and BN aerogel. The emerging applications of BNNS in different fields are then focused on, especially in barrier materials, dielectrics, catalysts, and thermal management.Boron nitride (BN) is an important material in the family of two-dimensional (2D) materials. Advanced applications of few-layer or monolayer BN nanosheet prepared by solution processed methods, including one-step sonication, surface modification, and ball-mill-assisted are rapidly emerging as an exciting area of research that is attracting considerable attention from both industry and academia.
      PubDate: 2017-06-19T02:20:01.200282-05:
      DOI: 10.1002/adfm.201701450
       
  • White Organic LED with a Luminous Efficacy Exceeding 100 lm W−1 without
           Light Out-Coupling Enhancement Techniques
    • Authors: Sheng-Fan Wu; Si-Hua Li, Ya-Kun Wang, Chen-Chao Huang, Qi Sun, Jiao-Jiao Liang, Liang-Sheng Liao, Man-Keung Fung
      Abstract: Luminous efficacy (LE), which is given by the ratio of luminous flux to power, is commonly used to measure the power consumption of a light source. Unfortunately, the LE of white organic light-emitting diodes (OLEDs) still lags behind those of inorganic LED for practically used (>100 lm W−1). In this paper, an ultraefficient white OLED is discussed based on a newly designed thermally activated delayed fluorescent exciplex host. The resulting white OLED delivers an unusually high forward-viewing LE of 105.0 lm W−1 and external quantum efficiency (EQE) ηext of ≈30% (without using any optical out-coupling techniques). As far as it is known, specifically, these efficiencies are the highest values among the published white OLEDs to date. Two-color warm white emission is realized with Commission International de I'Eclairage coordinates of (0.40, 0.48) at a brightness of 1000 cd m−2. Furthermore, the well-matched energy alignment endows the device with an extremely low turn-on voltage (≈2.5 V). Such high efficiencies and excellent device performance should benefit from the advantages of exciplex material solely used as the host. Therefore, this study anticipates that the findings have great potential to boost the LE of OLEDs, and more importantly, fulfill the power efficacy requirement for lighting applications.An outstanding blue exciplex, named mCP:B4PyMPM, is implemented as a host for white organic light-emitting diode (OLED). Super-high luminous efficacy of 105.0 lm W−1 and external quantum efficiency of>28% are realized without employing optical out-coupling techniques. Efficiency roll-off of mCP:B4PyMPM based OLEDs is relatively mild. Additionally, extremely low turn-on voltages (≈2.5 V) and warm white emission are also achieved.
      PubDate: 2017-06-14T01:41:04.455596-05:
      DOI: 10.1002/adfm.201701314
       
  • Plant-Based Hollow Microcapsules for Oral Delivery Applications: Toward
           Optimized Loading and Controlled Release
    • Authors: Michael G. Potroz; Raghavendra C. Mundargi, Jurriaan J. Gillissen, Ee-Lin Tan, Sigalit Meker, Jae H. Park, Haram Jung, Soohyun Park, Daeho Cho, Sa-Ik Bang, Nam-Joon Cho
      Abstract: Efficient oral administration of protein-based therapeutics faces significant challenges due to degradation from the highly acidic conditions present in the stomach and proteases present in the digestive tract. Herein, investigations into spike-covered sunflower sporopollenin exine capsules (SECs) for oral protein delivery using bovine serum albumin (BSA) as a model drug are reported and provide significant insights into the optimization of SEC extraction, SEC loading, and controlled release. The phosphoric-acid-based SEC extraction process is optimized. Compound loading is shown to be driven by the evacuation of air bubbles from SEC cavities through the porous SEC shell wall, and vacuum loading is shown to be the optimal loading method. Three initial BSA-loading proportions are evaluated, leading to a practical loading efficiency of 22.3 ± 1.5 wt% and the determination that the theoretical maximum loading is 46.4 ± 2.5 wt%. Finally, an oral delivery formulation for targeted intestinal delivery is developed by tableting BSA-loaded SECs and enteric coating. BSA release is inhibited for 2 h in simulated gastric conditions followed by 100% release within 8 h in simulated intestinal conditions. Collectively, these results indicate that sunflower SECs provide a versatile platform for the oral delivery of therapeutics.Porous microcapsules extracted from sunflower pollen are used to develop an effective oral drug delivery system for targeted delivery of proteins to the intestinal tract. Sporopollenin exine capsule (SEC) extraction and loading are analyzed to provide insights into these processes and allow optimization. Tableting and enteric coating of SECs are shown to inhibit protein release in simulated gastric conditions and allow for full release in simulated intestinal conditions.
      PubDate: 2017-06-07T08:00:03.306152-05:
      DOI: 10.1002/adfm.201700270
       
  • Multifunctional Molecular Beacon Micelles for Intracellular mRNA Imaging
           and Synergistic Therapy in Multidrug-Resistant Cancer Cells
    • Authors: Ruili Zhang; Shi Gao, Zhongliang Wang, Da Han, Lin Liu, Qingjie Ma, Weihong Tan, Jie Tian, Xiaoyuan Chen
      Abstract: Multidrug resistance (MDR) resulting from overexpression of P-glycoprotein (Pgp) transporters increases the drug efflux and thereby limits the chemotherapeutic efficacy. It is desirable to administer both an MDR1 gene silencer and a chemotherapeutic agent in a sequential way to generate a synergistic therapeutic effect in multidrug-resistant cancer cells. Herein, an anti-MDR1 molecular beacon (MB)-based micelle (a-MBM) nanosystem is rationally designed. It is composed of a diacyllipid core densely packed with an MB corona. One of Pgp-transportable agents, doxorubicin (DOX), is encapsulated in the hydrophobic core of the micelle and in the stem sequence of MB. The a-MBM-DOX nanosystem shows an efficient self-delivery, enhanced enzymatic stability, excellent target selectivity, and high drug-loading capacity. With its relatively high enzymatic stability, a-MBM-DOX initially facilitates intracellular MDR1 mRNA imaging to distinguish multidrug-resistant and non-multidrug-resistant cells and subsequently downregulates the MDR1 gene expression owing to an antisense effect. After that, the MB corona is degraded, destroying the micellar nanostructure and releasing DOX, which result in a high accumulation of DOX in OVCAR8/ADR cells and a high chemotherapeutic efficacy because of successful restoration of drug sensitivity. This micelle approach has the potential for both visualizing MDR1 mRNA and overcoming MDR in a sequential and synergistic way.Molecular beacon-based micelle system (a-MBM) presents its capability to combat multidrug resistance (MDR) in a sequential and synergistic way. With enhanced enzymatic stability, excellent target selectivity, and high drug-loading capacity, a-MBMs allows for visualization of MDR1 mRNA and specifically inhibits MDR1 gene expression. It also results in a high chemotherapeutic efficacy because of successful restoration of drug sensitivity.
      PubDate: 2017-05-30T13:53:00.956429-05:
      DOI: 10.1002/adfm.201701027
       
  • CuF2 as Reversible Cathode for Fluoride Ion Batteries
    • Authors: Duc Tho Thieu; Mohammed Hammad Fawey, Harshita Bhatia, Thomas Diemant, Venkata Sai Kiran Chakravadhanula, Rolf Jürgen Behm, Christian Kübel, Maximilian Fichtner
      Abstract: In the search for novel battery systems with high energy density and low cost, fluoride ion batteries have recently emerged as a further option to store electricity with very high volumetric energy densities. Among metal fluorides, CuF2 is an intriguing candidate for cathode materials due to its high specific capacity and high theoretical conversion potential. Here, the reversibility of CuF2 as a cathode material in the fluoride ion battery system employing a high F− conducting tysonite-type La0.9Ba0.1F2.9 as an electrolyte and a metallic La as an anode is investigated. For the first time, the reversible conversion mechanism of CuF2 with the corresponding variation in fluorine content is reported on the basis of X-ray photoelectron spectroscopy measurements and cathode/electrolyte interfacial studies by transmission electron microscopy. Investigation of the anode/electrolyte interface reveals structural variation upon cycling with the formation of intermediate layers consisting of i) hexagonal LaF3 and monoclinic La2O3 phases in the pristine interface; ii) two main phases of distorted orthorhombic LaF3 and monoclinic La2O3 after discharging; and iii) a tetragonal lanthanum oxyfluoride (LaOF) phase after charging. The fading mechanism of the cell capacity upon cycling can be explained by Cu diffusion into the electrolyte and side reactions due to the formation of the LaOF compound.The reversible conversion mechanism of CuF2 in novel fluoride ion battery system is reported. Investigation of the electrode/electrolyte interface reveals structural variation upon cycling. The fading mechanism of the CuF2/La0.9Ba0.1F2.9/La cell capacity upon cycling can be explained by Cu diffusion into the electrolyte and side reactions due to the formation of the lanthanum oxyfluoride compound.
      PubDate: 2017-05-04T06:16:34.613637-05:
      DOI: 10.1002/adfm.201701051
       
  • Anisotropy in Shape and Ligand-Conjugation of Hybrid Nanoparticulates
           Manipulates the Mode of Bio–Nano Interaction and Its Outcome
    • Authors: Xiaoyou Wang; Li Lin, Renfa Liu, Min Chen, Binlong Chen, Bo He, Bing He, Xiaolong Liang, Wenbing Dai, Hua Zhang, Xueqing Wang, Yiguang Wang, Zhifei Dai, Qiang Zhang
      Abstract: In an attempt to manipulate the biological features of nanomaterials via both anisotropic shape and ligand modification, four types of nanoparticulates with good morphological stability are designed and engineered, including hybrid nanospheres, nanodiscs, and nanodiscs with edge modification or plane modification of octa-arginine (R8) sequence. It is found that the R8 modification anisotropy can trigger huge differences in the endocytosis, intracellular trafficking, and even tissue penetration of nanoparticulates. From plane modification to edge modification of R8, the maximum increase in cell uptake is up to 17-fold, which is much more significant than shape anisotropy alone. On the other hand, six types of different cell lines are investigated to simulate biological microenvironment. It is demonstrated that the maximum difference in cell uptake among six cell lines is 12-fold. Three main driving forces are found to contribute to such bio–nano interactions. Based on the findings of this study, it seems possible to manipulate the biointeraction mode of nanomaterials and its output by regulating their anisotropy in both shape and ligand modification.Nanospheres, nanodiscs, and nanodiscs with edge modification or plane modification of octa-arginine sequence are prepared. From nanospheres to nanodiscs and from plane modification to edge modification, the cellular uptake increases 1.5- and 17-fold, respectively. Such alternations also affect the intracellular pathway and tumor penetration. The double effect of anisotropic shape and ligand-modification is significant and might be applied to manipulate the nanovector delivery.
      PubDate: 2017-05-04T06:16:10.142692-05:
      DOI: 10.1002/adfm.201700406
       
 
 
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