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CHEMISTRY (603 journals)                  1 2 3 4 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 5)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 25)
ACS Catalysis     Full-text available via subscription   (Followers: 27)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 15)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 24)
ACS Macro Letters     Full-text available via subscription   (Followers: 20)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 35)
ACS Nano     Full-text available via subscription   (Followers: 172)
ACS Photonics     Full-text available via subscription   (Followers: 7)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 18)
Acta Chemica Iasi     Open Access  
Acta Chimica Sinica     Full-text available via subscription  
Acta Chimica Slovaca     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 8)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Scientifica Naturalis     Open Access  
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 5)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 6)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 4)
Advanced Functional Materials     Hybrid Journal   (Followers: 43)
Advanced Science Focus     Free   (Followers: 3)
Advances in Chemical Engineering and Science     Open Access   (Followers: 50)
Advances in Chemical Science     Open Access   (Followers: 11)
Advances in Chemistry     Open Access   (Followers: 10)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 15)
Advances in Drug Research     Full-text available via subscription   (Followers: 21)
Advances in Enzyme Research     Open Access   (Followers: 5)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 12)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 15)
Advances in Nanoparticles     Open Access   (Followers: 12)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 14)
Advances in Polymer Science     Hybrid Journal   (Followers: 37)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 15)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 14)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Science and Technology     Full-text available via subscription   (Followers: 6)
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)
Alchemy : Jurnal Penelitian Kimia     Open Access  
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: 60)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 13)
American Journal of Chemistry     Open Access   (Followers: 23)
American Journal of Plant Physiology     Open Access   (Followers: 12)
American Mineralogist     Full-text available via subscription   (Followers: 8)
Anadolu University Journal of Science and Technology     Open Access  
Analyst     Full-text available via subscription   (Followers: 41)
Angewandte Chemie     Hybrid Journal   (Followers: 127)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 172)
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: 7)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 9)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 13)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Full-text available via subscription  
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 5)
Applied Spectroscopy     Full-text available via subscription   (Followers: 23)
Applied Surface Science     Hybrid Journal   (Followers: 22)
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: 4)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access   (Followers: 1)
Biochemical Pharmacology     Hybrid Journal   (Followers: 7)
Biochemistry     Full-text available via subscription   (Followers: 232)
Biochemistry Insights     Open Access   (Followers: 4)
Biochemistry Research International     Open Access   (Followers: 5)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 8)
Bioinspired Materials     Open Access   (Followers: 2)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 1)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access  
Biomacromolecules     Full-text available via subscription   (Followers: 17)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 11)
Biomedical Chromatography     Hybrid Journal   (Followers: 7)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 2)
BioNanoScience     Partially Free   (Followers: 4)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 100)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 87)
Bioorganic Chemistry     Hybrid Journal   (Followers: 9)
Biopolymers     Hybrid Journal   (Followers: 17)
Biosensors     Open Access   (Followers: 1)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 2)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 3)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 25)
Bulletin of the Korean Chemical Society     Hybrid Journal  
C - Journal of Carbon Research     Open Access   (Followers: 2)
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Full-text available via subscription   (Followers: 6)
Canadian Mineralogist     Full-text available via subscription   (Followers: 3)
Carbohydrate Research     Hybrid Journal   (Followers: 27)
Carbon     Hybrid Journal   (Followers: 66)
Catalysis for Sustainable Energy     Open Access   (Followers: 5)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 7)
Catalysis Science and Technology     Free   (Followers: 5)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 6)
Cellulose     Hybrid Journal   (Followers: 5)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription  
ChemCatChem     Hybrid Journal   (Followers: 6)
Chemical and Engineering News     Free   (Followers: 11)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 63)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 21)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 18)
Chemical Reviews     Full-text available via subscription   (Followers: 130)
Chemical Science     Open Access   (Followers: 18)
Chemical Technology     Open Access   (Followers: 11)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 4)
Chemical Week     Full-text available via subscription   (Followers: 7)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 52)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 25)
ChemInform     Hybrid Journal   (Followers: 6)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 5)
Chemistry & Biology     Full-text available via subscription   (Followers: 29)
Chemistry & Industry     Hybrid Journal   (Followers: 3)
Chemistry - A European Journal     Hybrid Journal   (Followers: 117)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 13)
Chemistry and Materials Research     Open Access   (Followers: 15)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 4)
Chemistry in Education     Open Access   (Followers: 2)
Chemistry International     Hybrid Journal   (Followers: 1)
Chemistry Letters     Full-text available via subscription   (Followers: 43)
Chemistry of Materials     Full-text available via subscription   (Followers: 152)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 8)
Chemistry-Didactics-Ecology-Metrology     Open Access  
ChemistryOpen     Open Access   (Followers: 1)
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: 6)
ChemPlusChem     Hybrid Journal  
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 3)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 10)
Chromatographia     Hybrid Journal   (Followers: 24)
Chromatography Research International     Open Access   (Followers: 5)
Clay Minerals     Full-text available via subscription   (Followers: 9)
Cogent Chemistry     Open Access  
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 9)
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 7)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 4)
Combustion Science and Technology     Hybrid Journal   (Followers: 19)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 1)
Composite Interfaces     Hybrid Journal   (Followers: 3)
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: 9)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 9)
Coordination Chemistry Reviews     Full-text available via subscription  
Copernican Letters     Open Access  
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 4)
Crystal Structure Theory and Applications     Open Access   (Followers: 2)
CrystEngComm     Full-text available via subscription   (Followers: 7)
Current Catalysis     Hybrid Journal   (Followers: 1)
Current Metabolomics     Hybrid Journal   (Followers: 3)
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 7)
Current Opinion in Molecular Therapeutics     Full-text available via subscription   (Followers: 14)
Current Research in Chemistry     Open Access   (Followers: 7)
Current Science     Open Access   (Followers: 40)
Dalton Transactions     Full-text available via subscription   (Followers: 17)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 11)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  
Drying Technology: An International Journal     Hybrid Journal   (Followers: 3)
Eclética Química     Open Access   (Followers: 1)
Ecological Chemistry and Engineering S     Open Access   (Followers: 2)
Ecotoxicology and Environmental Contamination     Open Access  
Educación Química     Open Access   (Followers: 1)
Education for Chemical Engineers     Hybrid Journal   (Followers: 4)
EDUSAINS     Open Access  
Elements     Full-text available via subscription   (Followers: 1)
Environmental Chemistry     Hybrid Journal   (Followers: 5)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 2)

        1 2 3 4 | Last

Journal Cover Advanced Functional Materials
  [SJR: 5.21]   [H-I: 203]   [43 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  [1611 journals]
  • Masthead: (Adv. Funct. Mater. 40/2016)
    • PubDate: 2016-10-25T11:30:42.231839-05:
      DOI: 10.1002/adfm.201670263
  • Controlled Modulation of Surface Coating and Surface Charging on Quantum
           Dots with Negatively Charged Gelatin for Substantial Enhancement and
           Reversible Switching in Photoluminescence
    • Authors: Shuhua Liu; Xiangyang Liu, Ming‐Yong Han
      Abstract: Here, the roles of coating and charging on the surface of CdSe quantum dots (QDs) are systematically investigated in tuning their emission via a simple change of pH in solution. A very thick layer of ZnS with a wide bandgap is chemically grown first to passivate the CdSe for retaining their high emission intensity, which is further encapsulated with a layer of degraded gelatin to achieve the phase transfer of QDs from hexane into aqueous solution. Interestingly, the degraded gelatin‐capped CdSe/ZnS QDs (i.e., gelatinated QDs) greatly enhance their emission by adjusting pH from acidic to basic but greatly quench their emission by adjusting pH from basic to acidic. This highly reversible switching in photoluminescence is demonstrated for five cycles without obvious deterioration. With the increase of pH, there is a great decrease in radiative relaxation lifetime but a great increase in nonradiative relaxation lifetime as measured by time‐resolved photoluminescence decays of the gelatinated QDs. As a result, the nonradiative lifetime becomes much longer than the radiative lifetime with the increase of pH so that the radiative emission occurs earlier before the nonradiative pathways take effect, resulting in greatly increased photoluminescence. Importantly, the successful demonstrations for the phase transfer of hydrophobic QDs into aqueous solution together with the reversible switching in photoluminescence arise from the reprocessing of acidic‐degraded gelatin in weak alkaline solution, resulting in a great reduction in isoelectric point of the sequential acidic‐alkaline degraded gelatin in free versus surface‐bound forms from 7 to 4. With the exposure of more negatively charged carboxylic groups externally, the negative surface charging is greatly increased with the increase of pH while it is greatly decreased with the decrease of pH, leading to reversible switching in photoluminescence.Gelatinated quantum dots with tunable negative charging at the surface are synthesized by using sequential acidic‐alkaline processed gelatin with a greatly reduced isoelectric point when chemically adsorbed on quantum dots. The increase of pH greatly enhances emission but the decrease of pH greatly weakens emission, demonstrating reversible switching in photoluminescence for five cycles without obvious deterioration.
      PubDate: 2016-10-24T08:50:24.613976-05:
      DOI: 10.1002/adfm.201604351
  • Direct Observation of Negative Capacitance in Polycrystalline
           Ferroelectric HfO2
    • Authors: Michael Hoffmann; Milan Pešić, Korok Chatterjee, Asif I. Khan, Sayeef Salahuddin, Stefan Slesazeck, Uwe Schroeder, Thomas Mikolajick
      Abstract: To further reduce the power dissipation in nanoscale transistors, the fundamental limit posed by the Boltzmann distribution of electrons has to be overcome. Stabilization of negative capacitance in a ferroelectric gate insulator can be used to achieve this by boosting the transistor gate voltage. Up to now, negative capacitance is only directly observed in polymer and perovskite ferroelectrics, which are incompatible with semiconductor manufacturing. Recently discovered HfO2‐based ferroelectrics, on the other hand, are ideally suited for this application because of their high scalability and semiconductor process compatibility. Here, for the first time, a direct measurement of negative capacitance in polycrystalline HfO2‐based thin films is reported. Decreasing voltage with increasing charge transients are observed in 18 and 27 nm thin Gd:HfO2 capacitors in series with an external resistor. Furthermore, a multigrain Landau–Khalatnikov model is developed to successfully simulate this transient behavior in polycrystalline ferroelectrics with nucleation limited switching dynamics. Structural requirements for negative capacitance in such materials are discussed. These results demonstrate that negative capacitance effects are not limited to epitaxial ferroelectrics, thus significantly extending the range of potential applications.Negative capacitance in ferroelectric materials can be directly measured by applying bipolar voltage pulses to a series connection of a resistor and a ferroelectric capacitor. This measurement is used to show negative capacitance in ferroelectric HfO2, which is a promising material for energy‐efficient nanoelectronic devices. Additionally, this proves that even polycrystalline ferroelectrics can exhibit negative capacitance phenomena.
      PubDate: 2016-10-24T08:45:26.014189-05:
      DOI: 10.1002/adfm.201602869
  • Melting of Colloidal Crystals
    • Authors: Feng Wang; Di Zhou, Yilong Han
      Abstract: Crystal melting is affected by many factors such as defects, surfaces, dimensionality, lattice structure, and particle interaction, and thus exhibits rich phenomenology. It is usually a first‐order phase transition which currently lacks a fundamental theory. Despite numerous studies over the past century, melting remains poorly understood at the microscopic level. Micrometer‐sized colloidal particles can be viewed as “big atoms” which can assemble into various phases. Their thermal motions can be directly imaged and tracked using optical microscopy. Hence, colloids are powerful model systems for studying phase transitions. Recent progress made in fabricating tunable micrometer‐sized colloidal particles has enabled the direct visualization of crystal melting with single‐particle dynamics. The observations have greatly expanded our understanding of melting kinetics. In this review, the experiments and simulations conducted on the superheating, melting, and premelting of colloidal crystals have been surveyed. The latest results on crystal melting obtained from colloidal model systems and challenges and future perspectives have been discussed.Crystal melting exhibits rich phenomenology but is much less studied than crystallization. Colloidal crystals are powerful model systems which enable the direct visualization of melting with single‐particle dynamics. This review covers the experiments and simulations about the homogeneous and heterogeneous melting and premelting of 3D and 2D colloidal crystals. The results greatly expanded the understanding of microscopic melting kinetics.
      PubDate: 2016-10-21T06:01:39.747082-05:
      DOI: 10.1002/adfm.201603077
  • Prolifera‐Green‐Tide as Sustainable Source for Carbonaceous Aerogels
           with Hierarchical Pore to Achieve Multiple Energy Storage
    • Authors: Jinfeng Cui; Yunlong Xi, Shuai Chen, Daohao Li, Xilin She, Jin Sun, Wei Han, Dongjiang Yang, Shaojun Guo
      Abstract: The increasing demand for efficient energy storage and conversion devices has aroused great interest in designing advanced materials with high specific surface areas, multiple holes, and good conductivity. Here, we report a new method for fabricating a hierarchical porous carbonaceous aerogel (HPCA) from renewable seaweed aerogel. The HPCA possesses high specific surface area of 2200 m2 g−1 and multilevel micro/meso/macropore structures. These important features make HPCA exhibit a reversible lithium storage capacity of 827.1 mAh g−1 at the current density of 0.1 A g−1, which is the highest capacity for all the previously reported nonheteroatom‐doped carbon nanomaterials. It also shows high specific capacitance and excellent rate performance for electric double layer capacitors (260.6 F g−1 at 1 A g−1 and 190.0 F g−1 at 50 A g−1), and long cycle life with 91.7% capacitance retention after 10 000 cycles at 10 A g−1. The HPCA also can be used as support to assemble Co3O4 nanowires (Co3O4@HPCA) for constructing a high performance pseudocapacitor with the maximum specific capacitance of 1167.6 F g−1 at the current density of 1 A g−1. The present work highlights the first example in using prolifera‐green‐tide as a sustainable source for developing advanced carbon porous aerogels to achieve multiple energy storage.Hierarchical porous carbonaceous aerogels (HPCAs) are scale‐up synthesized using prolifera‐green‐tide as a sustainable source. The HPCAs possess high specific surface area and multilevel micro‐, meso‐, and macropore structures. These important features make the HPCAs exhibit remarkable performance when used as anode materials for Li‐ion batteries and electrodes for supercapacitors.
      PubDate: 2016-10-21T02:15:48.26331-05:0
      DOI: 10.1002/adfm.201603933
  • Polymer‐Supramolecular Polymer Double‐Network Hydrogel
    • Authors: Wenxu Sun; Bin Xue, Ying Li, Meng Qin, Junyi Wu, Ke Lu, Junhua Wu, Yi Cao, Qing Jiang, Wei Wang
      Abstract: Mechanical properties of hydrogels are critical for their applications as articular cartilage regeneration scaffolds, because they provide not only the mechanical support, but also the mechanical cues essential to maintain the phenotype of cartilage‐forming cells. Inspired by the microscopic architecture of natural cartilage, here the engineering of a novel double‐network hydrogel with interconnected polymer‐supramolecular polymer double‐network (PS‐DN gel) for cartilage regeneration is reported. The polymer network is made of polyacrylamide and the supramolecular polymer network comprises of a kind of self‐assembled peptide fibers. Upon mechanical loading, the peptide fibers serve as sacrificial bonds to efficiently dissipate energy. They can quickly reform when mechanical load is released thanks to the fast and accurate peptide self‐assembly. These entail the PS‐DN gel of high mechanical strength of ≈0.32–0.57 MPa, fracture energy of ≈300–2670 J m−2, compressibility of ≈66%–90%, and fast recovery in seconds. The gel also shows significant energy dissipation, strain stiffening, and stress relaxation behaviors similar to articular cartilage. Moreover, the mechanical properties of the PS‐DN gel can be tailored by adjusting the chemical components of the gel. Therefore, this novel biomaterial represents a promising candidate for the regeneration of cartilage and other load bearing tissues.A novel double‐network hydrogel based on an interconnected polymer‐supramolecular polymer network is engineered by mimicking microscopic architecture of articular cartilage. The gel possesses high mechanical stiffness, fracture energy, compressibility, and fast recovery rate. It also shows significant energy dissipation, strain stiffening, and stress‐relaxation behaviors similar to articular cartilage, making it an ideal candidate for cartilage regeneration.
      PubDate: 2016-10-21T02:11:21.452401-05:
      DOI: 10.1002/adfm.201603512
  • High Strength Conductive Composites with Plasmonic Nanoparticles Aligned
           on Aramid Nanofibers
    • Authors: Jing Lyu; Xinzhi Wang, Lehao Liu, Yoonseob Kim, Ekembu K. Tanyi, Hang Chi, Wenchun Feng, Lizhi Xu, Tiehu Li, Mikhail A. Noginov, Ctirad Uher, Mark D. Hammig, Nicholas A. Kotov
      Abstract: Rapidly evolving fields of biomedical, energy, and (opto)electronic devices bring forward the need for deformable conductors with constantly rising benchmarks for mechanical properties and electronic conductivity. The search for conductors with improved strength and strain have inspired the multiple studies of nanocomposites and amorphous metals. However, finding conductors that defy the boundaries of classical materials and exhibit simultaneously high strength, toughness, and fast charge transport while enabling their scalable production, remains a difficult materials engineering challenge. Here, composites made from aramid nanofibers (ANFs) and gold nanoparticles (Au NPs) that offer a new toolset for engineering high strength flexible conductors are described. ANFs are derived from Kevlar macrofibers and retain their strong mechanical properties and temperature resilience. Au NPs are infiltrated into a porous, free‐standing aramid matrix, becoming aligned on ANFs, which reduces the charge percolation threshold and facilitates charge transport. Further thermal annealing at 300 °C results in the Au‐ANF composites with an electrical conductivity of 1.25 × 104 S cm−1 combined with a tensile strength of 96 MPa, a Young's modulus of 5.29 GPa, and a toughness of 1.3 MJ m−3. These parameters exceed those of most of the composite materials, and are comparable to those of amorphous metals but have no volume limitations. The plasmonic optical frequencies characteristic for constituent NPs are present in the composites with ANFs enabling plasmon‐based optoelectronic applications.A composite based on aramid nanofibers and gold nanoparticles reveals high mechanical properties and conductivity, being competitive with the best nanocomposites and amorphous metals. Gold nanoparticles are self‐assembled in chains on aramid nanofibers, which reduces the percolation threshold. Thermal annealing further facilitates charge transport. The scalable fabrication of the free‐standing composites sheets leads to ground‐breaking materials for wearable electronics and plasmonics.
      PubDate: 2016-10-21T02:05:32.71122-05:0
      DOI: 10.1002/adfm.201603230
  • A Composite of Carbon‐Wrapped Mo2C Nanoparticle and Carbon Nanotube
           Formed Directly on Ni Foam as a High‐Performance Binder‐Free Cathode
           for Li‐O2 Batteries
    • Authors: Qian‐Cheng Zhu; Shu‐Mao Xu, Michelle M. Harris, Chao Ma, Yu‐Si Liu, Xiao Wei, Hua‐Sheng Xu, Yong‐Xian Zhou, Yu‐Cai Cao, Kai‐Xue Wang, Jie‐Sheng Chen
      Abstract: Cathode design is indispensable for building Li‐O2 batteries with long cycle life. A composite of carbon‐wrapped Mo2C nanoparticles and carbon nanotubes is prepared on Ni foam by direct hydrolysis and carbonization of a gel composed of ammonium heptamolybdate tetrahydrate and hydroquinone resin. The Mo2C nanoparticles with well‐controlled particle size act as a highly active oxygen reduction reactions/oxygen evolution reactions (ORR/OER) catalyst. The carbon coating can prevent the aggregation of the Mo2C nanoparticles. The even distribution of Mo2C nanoparticles results in the homogenous formation of discharge products. The skeleton of porous carbon with carbon nanotubes protrudes from the composite, resulting in extra voids when applied as a cathode for Li‐O2 batteries. The batteries deliver a high discharge capacity of ≈10 400 mAh g−1 and a low average charge voltage of ≈4.0 V at 200 mA g−1. With a cutoff capacity of 1000 mAh g−1, the Li‐O2 batteries exhibit excellent charge–discharge cycling stability for over 300 cycles. The average potential polarization of discharge/charge gaps is only ≈0.9 V, demonstrating the high ORR and OER activities of these Mo2C nanoparticles. The excellent cycling stability and low potential polarization provide new insights into the design of highly reversible and efficient cathode materials for Li‐O2 batteries.A composite of carbon‐wrapped Mo2C nanoparticles and carbon nanotubes is prepared on Ni foam via a simple carbonization method. The even distribution of Mo2C nanoparticles with well‐controlled size shows enhanced oxygen reduction reaction/oxygen evolution reaction activities. The binder‐free cathode for Li‐O2 batteries results in high rate capability and outstanding long term cycle ability.
      PubDate: 2016-10-20T05:57:22.911076-05:
      DOI: 10.1002/adfm.201603462
  • The Root Causes of the Limited Stability of Solution-Coated Small-Molecule
           Organic Light-Emitting Devices: Faster Host Aggregation by
           Exciton–Polaron Interactions
    • Authors: Yong Joo Cho; Yingjie Zhang, Hyeonghwa Yu, Hany Aziz
      Abstract: The degradation mechanism is compared in organic light-emitting devices (OLEDs) fabricated by solution-coating to that in vacuum-deposited OLEDs. Devices comprising various host materials made by vacuum-deposition or solution-coating are investigated. Changes in devices electroluminescence (EL) spectra during prolonged electrical driving are compared and analyzed. Hole-only devices are also utilized, and employed to study the effects of charges and excitons, separately and combined. The results reveal that the faster degradation of solution-processed devices relative to their vacuum-deposited counterparts under electrical stress is due to a faster aggregation of the host materials. Interactions between excitons and polarons in the emitting layers of the devices induce this aggregation phenomenon. Although this phenomenon affects both vacuum-deposited and solution-coated emitting layers, it is found to occur much faster in the later. The findings shed light on the root causes of the limited stability of solution-processed OLEDs.The degradation mechanism by electrical aging in small-molecule organic light-emitting diodes using a solution-coated process are investigated. The results reveal that the faster degradation of solution-processed devices relative to their vacuum-deposited counterparts under electrical stress is due to a faster aggregation of the host materials.
      PubDate: 2016-10-19T02:20:34.903382-05:
      DOI: 10.1002/adfm.201603542
  • Inorganic and Hybrid Organo-Metal Perovskite Nanostructures: Synthesis,
           Properties, and Applications
    • Authors: Daniel Amgar; Sigalit Aharon, Lioz Etgar
      Abstract: Hybrid perovskite and all-inorganic perovskite have attracted much attention in recent years owing to their successful use in the photovoltaic field. Usually the perovskite is used in its bulk form, although recently, perovskites' nanocrystalline form has received increased attention. Recent developments in the evolving research field of nanomaterial-based perovskite are reviewed. Both hybrid organic-inorganic and all-inorganic perovskite nanostructures are discussed, as well as approaches to tune the optical properties by controlling the size and shape of perovskite nanostructures. In addition, chemical modifications can change the perovskite nanostructures' band-gap, similar to their bulk counterpart. Several applications, including light-emitting diodes, lasers, and detectors, demonstrate the latent potential of perovskite nanostructures.Recent developments in the evolving research field of nanomaterial-based perovskite are reviewed. Both hybrid organic-inorganic and all-inorganic perovskite nanostructures are discussed, as well as approaches to tune the optical properties by controlling the size and the shape of the perovskite nanostructures. Several applications, including light-emitting diodes, lasers, and detectors, demonstrate the latent potential of perovskite nanostructures.
      PubDate: 2016-10-18T07:10:43.352782-05:
      DOI: 10.1002/adfm.201603752
  • Solvent-Polarity-Engineered Controllable Synthesis of Highly Fluorescent
           Cesium Lead Halide Perovskite Quantum Dots and Their Use in White
           Light-Emitting Diodes
    • Authors: Guopeng Li; Hui Wang, Ting Zhang, Longfei Mi, Yugang Zhang, Zhongping Zhang, Wenjun Zhang, Yang Jiang
      Abstract: Cesium lead halide quantum dots (QDs) have tunable photoluminescence that is capable of covering the entire visible spectrum and have high quantum yields, which make them a new fluorescent materials for various applications. Here, the synthesis of CsPbX3 (X = Cl, Br, I, or mixed Cl/Br and Br/I) QDs by direct ion reactions in ether solvents is reported, and for the first time the synergetic effects of solvent polarity and reaction temperature on the nucleation and growth of QDs are demonstrated. The use of solvent with a low polarity enables controlled growth of QDs, which facilitates the synthesis of high-quality CsPbX3 QDs with broadly tunable luminescence, narrow emission width, and high quantum yield. A QD white LED (WLED) is demonstrated by coating the highly fluorescent green-emissive CsPbBr3 QDs together with red phosphors on a blue InGaN chip, which presents excellent warm white light emission with a high rendering index of 93.2 and color temperature of 5447 K, suggesting the potential applications of highly fluorescent cesium lead halide perovskite QDs as an alternative color converter in the fabrication of WLEDs.CsPbX3 quantum dots (QDs) have superior photophysics properties, including high quantum yield (up to 72%), wide color gamut (>NTSC standard), and narrow emission width (18–38 nm). The WLED based on CsPbBr3 QDs present excellent warm white light emission with a high rendering index of 93.2 and CIE coordinate of (0.3339, 0.3617).
      PubDate: 2016-10-18T07:05:33.089664-05:
      DOI: 10.1002/adfm.201603734
  • Liposome-Supported Peritoneal Dialysis for the Treatment of
           Hyperammonemia-Associated Encephalopathy
    • Authors: Valentina Agostoni; Soo Hyeon Lee, Vincent Forster, Meriam Kabbaj, Cristina R. Bosoi, Mélanie Tremblay, Matthias Zadory, Christopher F. Rose, Jean-Christophe Leroux
      Abstract: Hyperammonemia can lead to cerebral dysfunction, encephalopathy, coma, and death if not treated adequately. The poor prognosis associated with this condition reflects the unmet medical need for effective ammonia-lowering treatments. Here, the translational potential of liposome-supported peritoneal dialysis (LSPD), a recently-developed detoxification strategy for the removal of small ionizable molecules like ammonia, is described. Dialysis fluids supplemented with micrometer-sized, transmembrane pH-gradient liposomes are prepared via an innovative, osmotic shock-based method overcoming sterilization and long-term stability issues. LSPD is able to sequester ammonia in healthy rats in relation to the injected dose, buffering capacity of the liposomal core, and membrane composition. In a rat model of cirrhosis, LSPD outperforms conventional peritoneal dialysis in lowering plasmatic ammonia levels and attenuating brain edema. LSPD does not trigger any hypersensitive reaction in pigs, a side effect commonly observed upon the injection of colloids in this animal model and in humans. These findings support the development of LSPD for the treatment of hyperammonemia-induced encephalopathy.Liposome-supported peritoneal dialysis appears as an effective, safe, and easy-to-implement ammonia detoxification therapy. Transmembrane pH-gradient liposomes (acidic core) efficiently scavenge ammonia in the peritoneal space, outperforming conventional peritoneal dialysis, and significantly attenuating brain edema in cirrhotic rats. This study spans from the development of a manufacturing procedure suitable for clinical implementation to efficacy and safety assessment in appropriate animal models.
      PubDate: 2016-10-18T05:52:14.363434-05:
      DOI: 10.1002/adfm.201603519
  • Favorable Molecular Orientation Enhancement in Semiconducting Polymer
           Assisted by Conjugated Organic Small Molecules
    • Authors: Minji Kang; Jun-Seok Yeo, Won-Tae Park, Nam-Koo Kim, Dae-Hee Lim, Hansu Hwang, Kang-Jun Baeg, Yong-Young Noh, Dong-Yu Kim
      Abstract: A bimodal texturing effect of semiconducting polymers is investigated by incorporating conjugated small molecules to significantly improve the charge transport characteristics via formation of 3D transport pathways. Solution blending of the electron-transporting polymer, poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} (P(NDI2OD-T2)), with small molecular crystals of tetrathiafulvalene and tetracyanoquinodimethane is used, and the thin film microstructures are studied using a combination of atomic force microscopy, transmission electron microscopy, 2D grazing incidence X-ray diffraction, and surface-sensitive near-edge X-ray absorption fine structure. Blended thin films show edge-on and face-on bimodal texture with long-range order and microstructure packing orientation preferable for electron transport through the channel in organic field-effect transistors, which is confirmed by high electron mobility 1.91 cm2 V−1 s−1, small contact resistance, and low energetic disorder according to temperature dependence of the field-effect mobility. Structural changes suggest a 3D network charge transport model via lamella packing and bimodal orientation of the semiconducting polymers.Polymer morphology and molecular orientation are significantly changed by introducing conjugated planar small molecules into semiconducting polymer films. Face-on and edge-on bimodal texture with better long-range arrangement and ordered lamellar stacking enhances efficient charge transport in the polymer semiconductor of organic field-effect transistors.
      PubDate: 2016-10-18T01:15:29.127107-05:
      DOI: 10.1002/adfm.201603617
  • Hydroxyapatite/Mesoporous Graphene/Single-Walled Carbon Nanotubes
           Freestanding Flexible Hybrid Membranes for Regenerative Medicine
    • Authors: Rujing Zhang; Noah Metoki, Orna Sharabani-Yosef, Hongwei Zhu, Noam Eliaz
      Abstract: Freestanding flexible membranes based on biocompatible calcium phosphates are of great interest in regenerative medicine. Here, the authors report the first synthesis of well-aligned biomimetic hexagonal bars of hydroxyapatite (HAp) on flexible, freestanding mesoporous graphene/single-walled carbon nanotubes (MG/SWCNT) hybrid membranes. The chemical composition and surface morphology of the HAp coating resemble those of biological apatite. Nitrogen doping and oxygen plasma etching of the MG/SWCNT membranes increase the density of nucleation sites and yield more uniform coatings. This novel membrane favors the attachment and proliferation of human fetal osteoblast (hFOB) osteoprogenitor cells. When soaked in simulated body fluid, enhanced in vitro biomineralization occurs on the hybrid membranes. This hybrid membrane holds great promise in biomedical applications such as patches and strips for spine fusion, bone repair, and restoration of tooth enamel.Flexible, freestanding mesoporous graphene/single-walled carbon nanotubes hybrid membranes are electrodeposited with well-aligned biomimetic hydroxyapatite. Nitrogen doping and oxygen plasma etching of the substrates improve the coating. The coated membranes show excellent biocompatibility, bioactivity, and biomineralization in vitro. These novel membranes hold great promise in regenerative medicine applications such as bone repair and restoration of tooth enamel.
      PubDate: 2016-10-13T01:27:23.665663-05:
      DOI: 10.1002/adfm.201602088
  • Near-Field Energy Transfer Using Nanoemitters For Optoelectronics
    • Authors: Burak Guzelturk; Hilmi Volkan Demir
      Abstract: Effective utilization of excitation energy in nanoemitters requires control of exciton flow at the nanoscale. This can be readily achieved by exploiting near-field nonradiative energy transfer mechanisms such as dipole-dipole coupling (i.e., Förster resonance energy transfer) and simultaneous two-way electron transfer via exchange interaction (i.e., Dexter energy transfer). In this feature article, we review nonradiative energy transfer processes between emerging nanoemitters and exciton scavengers. To this end, we highlight the potential of colloidal semiconductor nanocrystals, organic semiconductors, and two-dimensional materials as efficient exciton scavengers for light harvesting and generation in optoelectronic applications. We present and discuss unprecedented exciton transfer in nanoemitter–nanostructured semiconductor composites enabled by strong light–matter interactions. We elucidate remarkably strong nonradiative energy transfer in self-assembling atomically flat colloidal nanoplatelets. In addition, we underscore the promise of organic semiconductor–nanocrystal hybrids for spin-triplet exciton harvesting via Dexter energy transfer. These efficient exciton transferring hybrids will empower desired optoelectronic properties such as long-range exciton diffusion, ultrafast multiexciton harvesting, and efficient photon upconversion, leading to the development of excitonic optoelectronic devices such as exciton-driven light-emitting diodes, lasers, and photodetectors.Utilization of near-field energy transfer is essential for photonic applications of emerging nanoemitters such as 2D semiconductors, colloidal nanocrystals, and organic semiconductors. This review captures recent developments in the field of energy transfer materials reaching unprecedented efficiency levels and highlights their exciting prospects for light generation and harvesting devices.
      PubDate: 2016-10-12T06:26:51.945032-05:
      DOI: 10.1002/adfm.201603311
  • Mapping Morphological and Structural Properties of Lead Halide Perovskites
           by Scanning Nanofocus XRD
    • Authors: Samuele Lilliu; Thomas G. Dane, Mejd Alsari, Jonathan Griffin, Alexander T. Barrows, Marcus S. Dahlem, Richard H. Friend, David G. Lidzey, J. E. Macdonald
      Abstract: Scanning nanofocus X-ray diffraction (nXRD) performed at a synchrotron is used to simultaneously probe the morphology and the structural properties of spin-coated CH3NH3PbI3 (MAPI) perovskite films for photovoltaic devices. MAPI films are spin-coated on a Si/SiO2/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) substrate held at different temperatures during the deposition in order to tune the perovskite film coverage. The films are then investigated using nXRD and scanning electron microscopy (SEM). The advantages of nXRD over SEM and other techniques are discussed. A method to visualize, selectively isolate, and structurally characterize single perovskite grains buried within a complex, polycrystalline film is developed. The results of nXRD measurements are correlated with solar cell device measurements, and it is shown that spin-coating the perovskite precursor solution at elevated temperatures leads to improved surface coverage and enhanced solar cell performance.Scanning nanofocus X-ray diffraction is used to simultaneously probe the morphology and the structural properties of spin-coated CH3NH3PbI3 perovskite films. The technique allows for perovskite grain segmentation based on a variety of structural properties and is used to understand why spin-coating the perovskite precursor solution at elevated temperature leads to improved surface coverage and enhanced solar cell performance.
      PubDate: 2016-10-12T06:26:34.023792-05:
      DOI: 10.1002/adfm.201603446
  • Nanostructuring Ferroelectrics via Focused Ion Beam Methodologies
    • Authors: Stuart R. Burns; J. Marty Gregg, Valanoor Nagarajan
      Abstract: As we reach the physical limit of Moore's law and silicon based electronics, alternative schemes for memory and sensor devices are being proposed on a regular basis. The properties of ferroelectric materials on the nanoscale are key to developing device applications of this intriguing material class, and nanostructuring has been readily pursued in recent times. Focused ion beam (FIB) microscopy is one of the most significant techniques for achieving this. When applied in tandem with the imaging and nanoscale manipulation afforded by proximal scanning force microscopy tools, FIB-driven nanoscale characterization has demonstrated the power and ability which simply may not be possible by other fabrication techniques in the search for innovative and novel ferroic phenomena. At the same time the process is not without pitfalls; it is time-consuming and success is not always guaranteed thus often being the bane in progress. This balanced review explores a brief history of the relationship between the FIB and ferroelectrics, the fascinating properties it has unveiled, the challenges associated with FIB that have led to alternative nanostructuring techniques and finally new ideas that should be explored using this exciting technique.Recently, the use of focused ion beam microscopy to nanostructure ferroelectric and multiferroic materials has unveiled some interesting new physics despite the initial problems faced with this fabrication technique. The basic principles, history, pitfalls and future promise of nanostructuring ferroic materials with focused ion beams are explored.
      PubDate: 2016-10-10T08:21:11.591301-05:
      DOI: 10.1002/adfm.201603812
  • Development of Therapeutic Small-Molecule Fluorophore for Cell
    • Authors: Xin Wang; Zelin Chen, Shenglin Luo, Taotao Jin, Yu Wang, Fuqin Chen, Liao Wu, Xu Tan, Chunmeng Shi
      Abstract: Cell transplantation holds great promise in regenerative medicine but restricted cell survival and tracking severely limited their therapeutic efficacy. The development of multifunctional agents to simultaneously address these challenges will be very helpful in cytotherapy. Near-infrared (NIR) imaging is being increasingly used for in vivo cell tracking, but the extensive cell contamination and potential cytotoxicity of current membrane lipophilic dyes severely limit their potentialuse in clinical applications. Here, a novel mitochondrial heptamethine dye, NIR cell protector-61 (NIRCP-61), is designed and synthesized via modification of N-alkyl side chains around a heptamethine core, which maintains the superior fluorescent imaging properties and significantly decreases cell contamination. Further, NIRCP-61 also significantly alleviates cell damage from acute oxidative stress and improves their therapeutic outcome in multiple animal models. This cytoprotective effect is mediated by evoking the intracellular antioxidant defense mechanisms of nuclear factor erythroid 2-related factor 2 (Nrf2) and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathways. NIRCP-61 is the first NIR agent that simultaneously meets the requirements for both cell tracking and cytoprotection. Therefore, NIRCP-61 may represent an attractive therapeutic fluorophore for cell transplantation and offers a convenient way to impel potential translation in clinical cell-based therapies.A small-molecule mitochondrial fluorophore, NIR cell protector-61, is characterized and found to have unique optical imaging and cytoprotective properties for cell transplantation. The fluorophore enhances cell survival by inducing endogenous cytoprotective molecules against oxidative stress via activating nuclear factor erythroid 2-related factor 2 and phosphoinositide 3-kinase/protein kinase B pathways, and subsequently augments tissue repair and regeneration.
      PubDate: 2016-10-10T07:51:10.727354-05:
      DOI: 10.1002/adfm.201600996
  • Tuning the Cell Adhesion on Biofunctionalized Nanoporous Organic
    • Authors: Sophia Schmitt; Julia Hümmer, Saskia Kraus, Alexander Welle, Sylvain Grosjean, Maximilian Hanke-Roos, Axel Rosenhahn, Stefan Bräse, Christof Wöll, Cornelia Lee-Thedieck, Manuel Tsotsalas
      Abstract: The ability to control the structure and surface chemistry of biomaterials on a molecular level is crucial for optimizing their performance. Here, a novel type of nanoporous organic framework that is suited for the fabrication of thin films is described. These surface-grafted gels (SURGELs) are prepared and functionalized using two orthogonal, metal-free click chemistries. The SURGELs are shown to be cytocompatible and to efficiently mediate adhesion of osteoblast-like cells. This process can be further enhanced by surface modification. In addition, the use of light-triggered reactions in combination with photomasks allows a patterned functionalization of the substrates. The potential to vary and exactly adjust the parameters within the SURGEL polymer network (including porosity and exact network topology on the nanometer scale as well as addressable functional groups) combined with the ability to functionalize their surfaces with any clickable biomolecule of choice in any desired pattern allow the targeted design of novel SURGEL-based biomaterials for applications in nanomedicine, tissue engineering scaffolds, wound dressing,and medical implants.Controlling the structure of biomaterials on a molecular level is crucial for their performance. The synthesis and post-synthetic modification of ideal network polymer thin films via orthogonal metal-free click chemistries is described and it is demonstrated that these surface-grafted gels (SURGELs) combined with post-synthetic surface biofunctionalization are suitable materials for implant coatings and nanomedicine.
      PubDate: 2016-10-10T07:50:59.118701-05:
      DOI: 10.1002/adfm.201603054
  • Recent Development of Transparent Conducting Oxide-Free Flexible Thin-Film
           Solar Cells
    • Authors: Wenxi Guo; Zijie Xu, Fayin Zhang, Shuyao Xie, Hongyao Xu, Xiang Yang Liu
      Abstract: The rapid development of the modern electronics gives rise to higher demands of flexible and wearable energy resources. Flexible transparent conducting electrodes (TCEs) are one of the essential components for flexible/wearable thin-film solar cells (SCs). In this regard, commercial indium tin oxide (ITO) on plastics has demonstrated superior optoelectronic performance although some drawbacks, i.e., the low abundance, film brittleness, low infrared transmittance, and poor chemical stability remain. On the other hand, several other transparent conducting oxide (TCO)-free transparent conductive materials, such as carbon nanotubes (CNTs), graphene, metallic nanowires (NWs), and conducting polymers, have experienced a rapid development to address these issues. In this feature article, an overview over the latest development of several flexible TCO-free thin film SCs, i.e., organic solar cells (OSCs), dye-sensitized solar cells (DSSCs), perovskite solar cells (pero-SCs), and fiber/wire-shaped SCs is provided. Three groups of flexible TCO-free thin film solar cells can be categorized according to their configurations: (i) front-side illuminated planar configuration; (ii) back-side illuminated planar configuration, and (iii) fiber-shaped solar cells (FSSCs). The article is focused on flexible TCO-free TCEs, including CNTs, graphene, metallic NW/nanotroughs, metallic grids, conducting polymers, metallic fiber, and carbon based fibers.Three groups of flexible transparent conducting oxide (TCO)-free thin film solar cells can be categorized according to their configurations: (i) front-side illuminated planar configuration; (ii) back-side illuminated planar configuration; and (iii) fiber-shaped solar cells. This article is focused on flexible TCO-free transparent conducting electrodes, including carbon nanotubes, graphene, metallic nanowires/nanotroughs, metallic grids, conducting polymers, metallic fiber, and carbon-based fibers.
      PubDate: 2016-10-10T07:46:00.391647-05:
      DOI: 10.1002/adfm.201603378
  • Self-Limiting Growth Nanoscale Coordination Polymers for Fluorescence and
           Magnetic Resonance Dual-Modality Imaging
    • Authors: Yong-Mei Wang; Wei Liu, Xue-Bo Yin
      Abstract: The size and shape of coordination polymers (CPs) are often tuned by external factors including reaction temperature, reaction time, precursor ratio, auxiliary ligand, and surfactant. Here, a self-limiting growth of uniform nanoscale CPs (NCPs) spheres with Gd3+ and Ru[4,4′-(COOH)2 bipyridyl(bpy)]32+ (LRu) as precursors is reported. Sexadentate LRu and nine-coordinating Gd3+ play key roles in the formation of the NCPs via a simple and robust self-limiting procedure. Therefore, the formation of NCP spheres is almost unaffected in the reaction temperature of 100–160 °C for 1–6 h. Moreover, no auxiliary ligand or surfactant is required, whereas high yield and simple procedure are obtained. The red fluorescence of LRu and high longitudinal relaxivity of Gd3+ remain in the NCPs, which are therefore examined as fluorescence-magnetic resonance (MR) dual-modality imaging probes. The structural merits of the NCPs enable high MR contrast efficiency. Red emission avoids the auto-fluorescence and light scattering from tissues and realizes low-background imaging. The low toxicity and background, and high imaging efficiency of the NCPs are confirmed using HepG2 cells, zebrafish, and tumor-bearing mice as models.Uniform nanoscale coordination polymers (NCPs) are robustly prepared with a Ru complex and Gd3+ for use as a dual-modality imaging probe. The excellent red fluorescence and high longitudinal relaxivity of the NCPs realize fluorescence-magnetic resonance dual-modality imaging with low background and toxicity.
      PubDate: 2016-10-10T01:51:54.147193-05:
      DOI: 10.1002/adfm.201602925
  • Functionalization of Silk Fibroin Materials at Mesoscale
    • Authors: Naibo Lin; Liwei Cao, Qiaoling Huang, Changyong Wang, Yan Wang, Jin Zhou, Xiang-Yang Liu
      Abstract: Silk fibers spun by silkworms or spiders at ambient temperature display unique mechanical strength, excellent biocompatibility and optical transparency, which offer unconventional interfaces to soft and curved biological systems. In comparison with conventional materials, the performance of soft matter, i.e., animal silks, is mainly determined by the structure at the mesoscale. To further extend the applications, functionalization of silk materials becomes is required, and mesoscopic material assembly (MMA) was developed for this task. This feature article provides an overview on the principles and strategies concerning MMA, and some typical examples of functionalizing silk fibroin materials. The main strategies of MMA include in vivo and in vitro assemblies, and can be implemented by the three different paths: (1) molecular recognition, (2) surface functionalization of nanomaterials, or (3) foreign molecule mediation. The cases include the functionalization of silk fibroin materials by one/two-photon fluorescent molecules, quantum dots (QDs) and gold clusters, etc. The applications of these functionalized materials in bio waveguide, white-light-emitting devices, bioimaging, were also highlighted. MMA provides a practical tool for the production of the functionalized biocompatible materials, which can be further applied to fabricate high-performance bio integrated devices used in consumer electronics, and biomedical diagnosis, as well as human-machine interfaces.Functional silk materials can be fabricated in vitro and in vivo by material assembly on the mesoscopic scale based on the understanding and controlling of the hierarchical structure. The knowledge of the functionalization of silk by mesoscopic material assembly should be translated in such a way that it can facilitate functionalization and rational design of materials in a controllable manner.
      PubDate: 2016-10-07T01:53:39.988149-05:
      DOI: 10.1002/adfm.201603826
  • Near-Infrared Photoresponse of One-Sided Abrupt MAPbI3/TiO2 Heterojunction
           through a Tunneling Process
    • Authors: Keyou Yan; Zhanhua Wei, Tiankai Zhang, Xiaoli Zheng, Mingzhu Long, Zefeng Chen, Weiguang Xie, Teng Zhang, Yuda Zhao, Jianbin Xu, Yang Chai, Shihe Yang
      Abstract: Trap states in semiconductors usually degrade charge separation and collection in photovoltaics due to trap-mediated nonradiative recombination. Here, it is found that perovskite can be heavily doped in low concentration with non-ignorable broadband infrared absorption in thick films and their trap states accumulate electrons through infrared excitation and hot carrier cooling. A hybrid one-sided abrupt perovskite/TiO2 p-N heterojunction is demonstrated that enables partial collection of these trap-filled charges through a tunneling process instead of detrimental recombination. The tunneling is from broadband trap states in the wide depleted p-type perovskite, across the barrier of the narrow depleted TiO2 region (
      PubDate: 2016-10-06T07:10:36.636128-05:
      DOI: 10.1002/adfm.201602736
  • Facile Fabrication of High-Density Sub-1-nm Gaps from Au Nanoparticle
           Monolayers as Reproducible SERS Substrates
    • Authors: Shaorong Si; Wenkai Liang, Yinghui Sun, Jing Huang, Weiliang Ma, Zhiqiang Liang, Qiaoliang Bao, Lin Jiang
      Abstract: The fabrication of ultrasmall nanogaps (sub-1 nm) with high density is of significant interest and importance in physics, chemistry, life science, materials science, surface science, nanotechnology, and environmental engineering. However, it remains a challenge to generate uncovered and clean sub-1-nm gaps with high density and uniform reproducibility. Here, a facile and low-cost approach is demonstrated for the fabrication of high-density sub-1-nm gaps from Au nanoparticle monolayers as reproducible surface-enhanced Raman scattering (SERS) substrates. Au nanoparticles with larger diameters possess lower surface charge, thus the obtained large-area nanoparticle monolayer generates a high-density of sub-1-nm gaps. In addition, a remarkable SERS performance with a 1011 magnitude for the Raman enhancement is achieved for 120 nm Au nanoparticle monolayers due to the dramatic increase in the electromagnetic field enhancement when the obtained gap is smaller than 0.5 nm. The Au nanoparticle monolayer is also transferred onto a stretchable PDMS substrate and the structural stability and reproducibility of the high-density sub-1-nm gaps in Au monolayer films are illustrated. The resultant Au nanoparticle monolayer substrates with an increasing particle diameter exhibit tunable plasmonic properties, which control the plasmon-enhanced photocatalytic efficiency for the dimerization of p-aminothiophenol. The findings reported here offer a new opportunity for expanding the SERS application.A facile and low-cost approach is demonstrated for the fabrication of high-density sub-1-nm gaps from Au nanoparticle monolayers as reproducible surface-enhanced Raman scattering (SERS) substrates. Remarkable SERS performance with a 1011 magnitude Raman enhacement is achieved for 120 nm Au nanoparticle monolayers due to the dramatic increase in the electromagnetic field enhancement when the obtained gap is smaller than 0.5 nm.
      PubDate: 2016-10-06T07:01:12.158384-05:
      DOI: 10.1002/adfm.201602337
  • Design and Synthesis of “All-in-One” Multifunctional FeS2
           Nanoparticles for Magnetic Resonance and Near-Infrared Imaging Guided
           Photothermal Therapy of Tumors
    • Authors: Zhouqi Meng; Fang Wei, Wujun Ma, Nuo Yu, Peiling Wei, Zhaojie Wang, Yueqin Tang, Zhigang Chen, Huiping Wang, Meifang Zhu
      Abstract: The ideal theranostic nanoplatform for tumors is a single nanoparticle that has a single semiconductor or metal component and contains all multimodel imaging and therapy abilities. The design and preparation of such a nanoparticle remains a serious challenge. Here, with FeS2 as a model of a semiconductor, the tuning of vacancy concentrations for obtaining “all-in-one” type FeS2 nanoparticles is reported. FeS2 nanoparticles with size of ≈30 nm have decreased photoabsorption intensity from the visible to near-infrared (NIR) region, due to a low S vacancy concentration. By tuning their shape/size and then enhancing the S vacancy concentration, the photoabsorption intensity of FeS2 nanoparticles with size of ≈350 nm (FeS2-350) goes up with the increase of the wavelength from 550 to 950 nm, conferring the high NIR photothermal effect for thermal imaging. Furthermore, this nanoparticle has excellent magnetic properties for T2-weighted magnetic resonance imaging (MRI). Subsequently, FeS2-350 phosphate buffer saline (PBS) dispersion is injected into the tumor-bearing mice. Under the irradiation of 915-nm laser, the tumor can be ablated and the metastasis lesions in liver suffer significant inhibition. Therefore, FeS2-350 has great potential to be used as novel “all-in-one” multifunctional theranostic nanoagents for MRI and NIR dual-modal imaging guided NIR-photothermal ablation therapy (PAT) of tumors.“All-in-one” multifunctional FeS2 nanoparticles with size of ≈350 nm (FeS2-350) are prepared and their photoabsorption intensity goes up with the increase of the wavelength from 550 to 950 nm. They can be used as a novel theranostics nanoagent for simultaneous magnetic resonance imaging (MRI) and near-infrared dual-modal imaging and for photothermal therapy of tumors.
      PubDate: 2016-10-06T06:21:17.062999-05:
      DOI: 10.1002/adfm.201603776
  • In Situ Confinement Pyrolysis Transformation of ZIF-8 to Nitrogen-Enriched
           Meso-Microporous Carbon Frameworks for Oxygen Reduction
    • Authors: Qingxue Lai; Yingxuan Zhao, Yanyu Liang, Jianping He, Junhong Chen
      Abstract: Metal organic framework (MOF)-derived nitrogen-enriched nanocarbons have been proposed as promising metal-free electrocatalysts for oxygen reduction reaction. However, the characteristic microporous feature of MOF-derived carbon determined by the MOF structure significantly hinders the mass transfer and exposure of active sites, resulting in unsatisfactory electrocatalytic performance. Here an in situ confinement pyrolysis strategy that can simply but efficiently transform monodisperse ZIF-8 polyhedrons to nitrogen-enriched meso-microporous carbon (NEMC) frameworks is reported. Using this strategy, 3D NEMC frameworks, 1D NEMC fibers, and 2D NEMC on graphene (NEMC/G) can be successfully obtained. As a metal-free elctrocatalyst, optimized NEMC/G can reach a comparable electrocatalytic activity with superior stability and methanol resistance to commercial 30 wt% Pt/C catalyst in 0.1 m KOH solution. Such enhanced performance can be ascribed to the stable and highly open network consisting of NEMC and G with fully exposed active sites, thereby leading to durable catalytic activity.In situ confinement pyrolysis strategy without using any template is proposed to construct nitrogen-enriched meso-microporous carbon (NEMC) frameworks from a metal organic framework for use as metal-free oxygen reduction electrocatalysts. Uing a very simple but effective strategy, the NEMC catalysts with well-defined 1D–3D morphology can be easily realized and they demonstrate excellent electrocatalytic performance through optimizing the channel structures and nitrogen-doped sites.
      PubDate: 2016-10-06T06:20:49.884659-05:
      DOI: 10.1002/adfm.201603607
  • Modulating the Photocatalytic Activity of Graphene Quantum Dots via Atomic
           Tailoring for Highly Enhanced Photocatalysis under Visible Light
    • Authors: Su-Ji Jeon; Tae-Woog Kang, Jong-Min Ju, Man-Jin Kim, Jung Hyun Park, Faizan Raza, Juhee Han, Hye-Rim Lee, Jong-Ho Kim
      Abstract: Precise control over doping of photocatalysts is required to modulate their photocatalytic activity in visible light-driven reactions. Here, a single precursor-employing bottom-up approach is developed to produce different heteroatom-doped graphene quantum dots (GQDs) with unique photocatalytic activities. The solvothermal reaction of a norepinephrine precursor with redox active and condensable moieties effectively produces both nitrogen/sulfur codoped GQDs (NS-GQDs) and nitrogen-doped GQDs (N-GQDs) by simply varying solvents (from dimethyl sulfoxide to water) under microwave irradiation. As-prepared NS-GQDs and N-GQDs show similar lateral sizes (3–4 nm) and heights (1–2 nm), but they include different dopant types and doping constitution and content, which lead to changes in photocatalytic activity in aerobic oxidative coupling reactions of various amines. NS-GQDs exhibit much higher photocatalytic activity in reactions under visible light than N-GQDs and oxygen-doped GQDs (O-GQDs). The mechanism responsible for the outstanding photocatalytic activity of NS-GQDs in visible light-driven oxidative coupling reactions of amines is also fully investigated.Modulation of the photocatalytic activity of heteroatom-doped graphene quantum dots (GQDs) is reported. A single precursor, norepinephrine, is used to effectively produce N,S-co-doped GQDs and N-doped GQDs under microwave irradiation. Tailoring dopant types, constitution, and content imparts much higher photocatalytic activity to N,S-codoped GQDs than N-doped GQDs and O-doped GQDs in the visible-light-driven oxidative coupling reaction of various amines.
      PubDate: 2016-10-06T06:20:34.880255-05:
      DOI: 10.1002/adfm.201603803
  • Phase Inversion: A Universal Method to Create High-Performance Porous
           Electrodes for Nanoparticle-Based Energy Storage Devices
    • Authors: Xiaofei Yang; Yuqing Chen, Meiri Wang, Hongzhang Zhang, Xianfeng Li, Huamin Zhang
      Abstract: The intrinsic properties of nanoscale active materials are always excellent for energy storage devices. However, the accompanying problems of ion/electron transport limitation and active materials shedding of the whole electrodes, especially for high-loaded electrode composed of nanoparticles with high specific surface area, bring down their comprehensive performance for practical applications. Here, this problem is solved with the as proposed “phase inversion” method, which allows fabrication of tricontinuous structured electrodes via a simple, convenient, low cost, and scalable process. During this process, the binder networks, electron paths, and ion channels can be separately interconnected, which simultaneously achieves excellent binding strength and ion/electron conductivity. This is verified by constructing electrodes with sulfur/carbon (S/C) and Li3V2(PO4)3/C (LVP/C) nanoparticles, separately delivering 869 mA h g−1 at 1 C in Li–S batteries and 100 mA h g−1 at 30 C in Li–LVP batteries, increasing by 26% and 66% compared with the traditional directly drying ones. Electrodes with 7 mg cm−2 sulfur and 11 mg cm−2 LVP can also be easily coated on aluminum foil, with excellent cycling stability. Phase inversion, as a universal method to achieve high-performance energy storage devices, might open a new area in the development of nanoparticle-based active materials.A scalable, energy-saving and environmentally friendly phase inversion method is successfully used to prepare electrodes (PIEs) with tricontinuous phase structure. The as-prepared electrodes have increased adhesive strength and improved Li+/e− transport, which leads to high active material loadings, excellent cycling stability, and good C-rate performance for both Li–S batteries and Li-ion batteries.
      PubDate: 2016-10-06T06:16:25.057366-05:
      DOI: 10.1002/adfm.201604229
  • (Magic Dopant) Amphoteric Behavior of a Redox-Active Transition Metal Ion
           in a Perovskite Lattice: New Insights on the Lattice Site Occupation of
           Manganese in SrTiO3
    • Authors: Russell A. Maier; Aaron C. Johnston-Peck, Matthew P. Donohue
      Abstract: It is demonstrated that a transition metal redox-active ion can exhibit amphoteric dopant substitution in the SrTiO3 perovskite lattice. In stoichiometric SrTiO3, the manganese dopant is preferably accommodated through isovalent substitution as Mn2+ on the strontium site and as Mn4+ on the titanium site. Previous studies have suggested that either type of substitution is possible for compositions with tailored Sr/Ti stoichiometry. Using electron paramagnetic resonance (EPR) spectroscopy, the site occupancy of dilute concentrations of manganese is investigated in SrTiO3 as a function of the Sr/Ti ratio. The tuned Sr/Ti ratio can be used to manipulate the nature of the manganese substitution, and it is shown that Sr-rich compositions (Sr/Ti > 1.001) processed in air result in B-site isovalent doping. For B-site substituted manganese ions, a new EPR signal for aliovalent Mn2+ is observed in compositions annealed under reducing atmosphere. The concentration of oxygen vacancies observed with EPR is also shown to depend on the Sr/Ti stoichiometry. With improved control over the site of substitution and valence state, doping with a transition metal redox-active ion may facilitate the ability to engineer new electronic functionality into the perovskite lattice.A transition metal redox-active amphoteric dopant is investigated in the perovskite lattice. Electron paramagnetic resonance is used to determine the site occupancy of manganese ions doped in dilute concentrations in the SrTiO3 host lattice as a function of Sr/Ti cation non-stoichiometry.
      PubDate: 2016-10-05T08:20:41.191563-05:
      DOI: 10.1002/adfm.201602156
  • Vertical 2D MoO2/MoSe2 Core–Shell Nanosheet Arrays as High-Performance
           Electrocatalysts for Hydrogen Evolution Reaction
    • Authors: Xiaoshuang Chen; Guangbo Liu, Wei Zheng, Wei Feng, Wenwu Cao, Wenping Hu, PingAn Hu
      Abstract: Electrochemical water splitting is very attractive for green fuel energy production, but the development of active, stable, and earth-abundant catalysts for the hydrogen evolution reaction (HER) remains a major challenge. Here, core–shell nanostructured architectures are used to design and fabricate efficient and stable HER catalysts from earth-abundant components. Vertically oriented quasi-2D core–shell MoO2/MoSe2 nanosheet arrays are grown onto insulating (SiO2/Si wafer) or conductive (carbon cloth) substrates. This core–shell nanostructure array architecture exhibits synergistic properties to create superior HER performance, where high density structural defects and disorders on the shell generated by a large crystalline mismatch of MoO2 and MoSe2 act as multiple active sites for HER, and the metallic MoO2 core facilitates charge transport for proton reduction while the vertical nanosheet arrays ensure fully exposed active sites toward electrolytes. As a HER catalyst, this electrode exhibits a low Tafel slope of 49.1 mV dec−1, a small onset potential of 63 mV, and an ultralow charge transfer resistance (Rct) of 16.6 Ω at an overpotential of 300 mV with a long cycling durability for up to 8 h. This work suggests that a quasi 2D core–shell nanostructure combined with a vertical array microstructure is a promising strategy for efficient water splitting electrocatalysts with scale-up potential.Vertically aligned quasi 2D MoO2/MoSe2 core–shell nanosheet arrays have a synergistic effect that results in outstanding hydrogen evolution reaction performance. Structural defects and disorders on the shell, generated by a large crystalline mismatch of MoO2 and MoSe2, act as multiple active sites and the metallic MoO2 core facilitates charge transport for proton reduction while vertical arrays ensure full exposure of the active sites toward electrolytes.
      PubDate: 2016-10-04T08:46:05.502025-05:
      DOI: 10.1002/adfm.201603674
  • A Sequentially Triggered Nanosystem for Precise Drug Delivery and
           Simultaneous Inhibition of Cancer Growth, Migration, and Invasion
    • Authors: Ting Liu; Lanhai Lai, Zhenhuan Song, Tianfeng Chen
      Abstract: The rational design of cancer-targeted and bioresponsive drug delivery vehicles can enhance the anticancer efficacy of conventional chemotherapeutics and reduce their adverse side effects. However, the complexity of precise delivery and the ability to trigger drug release in specific tumor sites remain a challenging puzzle. Here, a sequentially triggered nanosystem composed of HER2 antibody with disulfide linkage as a surface decorator (HER2@NPs) is constructed for precise drug delivery and the simultaneous inhibition of cancer growth, migration, and invasion. The nanosystem actively accumulates in cancer cells, undergoes self-immolative cleavage in response to biological thiols, and is degraded to form small nanoparticles. After internalization by receptor-mediated endocytosis, the nanoparticles further disassemble under acidic conditions in the presence of lysozymes and cell lysates, leading to sequentially triggered drug release. The released payload triggers overproduction of reactive oxygen species and activates p53 and MAPKs pathways to induce cancer cell apoptosis. Moreover, HER2@NPs markedly suppress the migration and invasion of human bladder cancer cells at nontoxic concentrations. HER2@NPs demonstrate potent in vivo anticancer efficacy, but show no obvious histological damage to the major organs. Taken together, this study provides a valid tactic for the rational design of sequentially triggered nanosystems for precise drug delivery and cancer therapy.The rational design of a sequentially triggered selenium nanoparticle drug delivery system as the carrier of copper complexes for precise drug delivery and simultaneous inhibition of cancer growth, migration, and invasion is presented. This system allows direct fluorescence monitoring of the selective cellular uptake and co-localization of the nanoparticles in cancer cells.
      PubDate: 2016-10-04T08:45:58.760652-05:
      DOI: 10.1002/adfm.201604206
  • Color-Temperature Tuning and Control of Trichromatic White Light Emission
           from a Multisegment ZnCdSSe Heterostructure Nanosheet
    • Authors: Sunay Turkdogan; Fan Fan, Cun-Zheng Ning
      Abstract: Tuning and control of color temperature of trichromatic white light emission is demonstrated for the first time from a single ZnCdSSe nanosheet realized by a novel growth method using chemical vapor deposition (CVD). The nanosheets have thicknesses in the range of 60–350 nm and lateral dimensions of tens of micrometers. These nanosheet structures with three or more parallel segments are able to emit the three primary colors of light from a monolithic body and the combination of the emitted light appears as white. Due to temperature dependence of the alloy composition and the spatial profile of the temperature in the CVD chamber, alloy compositions and the widths of individual segments can be controlled by the substrate locations and the growth time, respectively. Such control determines the emission color and relative intensity of each segment, thus resulting in the tuning of the color temperature of the white light, or in the realization of any visible colors. Trichromatic white light emission is demonstrated with the correlated color temperature covering an extensive range from 2700 to 14 400 K using various growth parameters. In addition, a dynamic tuning of colors and color temperature is demonstrated by sweeping a pump beam across a single nanosheet.Tuning and control of the color temperature of white light emission from a monolithic heterostructure nanosheet is demonstrated. Correlated color temperature tunable between 2700 and 14400 K is achieved using a simple but versatile growth method. Additionally, dynamical tuning of colors is demonstrated by adjusting the relative pumping power of each segment via a simple laser beam sweeping method.
      PubDate: 2016-10-04T08:45:49.089225-05:
      DOI: 10.1002/adfm.201603620
  • The Effect of the Microstructure on Trap-Assisted Recombination and Light
           Soaking Phenomenon in Hybrid Perovskite Solar Cells
    • Authors: Shuyan Shao; Mustapha Abdu-Aguye, Tejas S. Sherkar, Hong-Hua Fang, Sampson Adjokatse, Gert ten Brink, Bart J. Kooi, L. Jan Anton Koster, Maria Antonietta Loi
      Abstract: Despite the rich experience gained in controlling the microstructure of perovskite films over the past several years, little is known about how the microstructure affects the device properties of perovskite solar cells (HPSCs). In this work, the effects of the perovskite film microstructure on the charge recombination and light-soaking phenomenon in mixed halide HPSCs are investigated. Devices with noncompact perovskite morphology show a severe light soaking effect, with the power conversion efficiency (PCE) improved from 3.7% to 11.6% after light soaking. Devices with compact perovskite morphology show a negligible light soaking effect, with PCE slightly increased from 11.4% to 11.9% after light soaking. From device investigations, photoluminescence, and impedance spectroscopy measurements, it is demonstrated that interface electron traps at the grain boundaries as well as at the crystal surface dominate the light soaking effect. Severe trap-assisted recombination takes place in HPSCs using noncompact films, while it is effectively eliminated in devices with compact films. Moreover, how the grain size of the perovskite film affects the light soaking phenomenon is investigated. In the case of compact perovskite films, the size of the grains has a limited effect on the light soaking. In these compact films, grains are fused and trap states are effectively reduced.The effects of the perovskite film microstructure on the charge recombination and light-soaking phenomenon are investigated in hybrid perovskite solar cells (HPSCs). It is demonstrated that interface electron traps at the grain boundaries as well as at the crystal surface dominate the light soaking effect.
      PubDate: 2016-10-04T08:40:43.85132-05:0
      DOI: 10.1002/adfm.201602519
  • Programing Performance of Silk Fibroin Materials by Controlled Nucleation
    • Authors: Zhengwei Chen; Honghao Zhang, Zaifu Lin, Youhui Lin, Jan H. van Esch, Xiang Yang Liu
      Abstract: To examine the mechanism of the network formation of silk fibroin (SF), monodispersed colloidal particles (MDCPs) are used as well defined foreign substrates to quantify their effect on the primary nucleation of β-crystallites in molecular networks (silk nanofibrils) and the hierarchical network formation of SF. It follows that MDCPs are capable of accelerating the SF gelation by reducing the multistep nucleation barrier, which gives rise to a high density of silk fibril domain networks due to the increase of primary nucleation sites. Consequently, through governing the change in the hierarchical mesoscopic structure, the macroscopic performance of silk materials (e.g., the rheological properties of SF hydrogels and the tensile stress of fibers) can be controlled directly. As SF hydrogels represent a typical example of weak fibril domain–domain network interactions, the increase of fibril domain density leads to weaker gels. On the other hand, SF fibers correspond to strong fibril domain–domain network interactions, the increase of fibril domain density ends up with much tougher fibers. The knowledge obtained provides a facile strategy in controlling the complex hierarchical structure and macroscopic performance of SF materials, and offers useful routes for general design and functionalization of soft materials.With the aid of monodispersed colloidal particles, silk fibroin gelation is greatly enhanced via the promotion of the nucleation of β-crystallites. Furthermore, by controlling the nucleation promotion centers, the mesoscopic structure of silk materials is manipulated to acquire the desired performance.
      PubDate: 2016-10-04T03:16:42.703412-05:
      DOI: 10.1002/adfm.201602908
  • Highly Efficient Electrocatalysts for Oxygen Reduction Reaction Based on
           1D Ternary Doped Porous Carbons Derived from Carbon Nanotube Directed
           Conjugated Microporous Polymers
    • Authors: Yafei He; Dominik Gehrig, Fan Zhang, Chenbao Lu, Chao Zhang, Ming Cai, Yuanyuan Wang, Frédéric Laquai, Xiaodong Zhuang, Xinliang Feng
      Abstract: One-dimensional (1D) porous materials have shown great potential for gas storage and separation, sensing, energy storage, and conversion. However, the controlled approach for preparation of 1D porous materials, especially porous organic materials, still remains a great challenge due to the poor dispersibility and solution processability of the porous materials. Here, carbon nanotube (CNT) templated 1D conjugated microporous polymers (CMPs) are prepared using a layer-by-layer method. As-prepared CMPs possess high specific surface areas of up to 623 m2 g−1 and exhibit strong electronic interactions between p-type CMPs and n-type CNTs. The CMPs are used as precursors to produce heteroatom-doped 1D porous carbons through direct pyrolysis. As-produced ternary heteroatom-doped (B/N/S) 1D porous carbons possess high specific surface areas of up to 750 m2 g−1, hierarchical porous structures, and excellent electrochemical-catalytic performance for oxygen reduction reaction. Both of the diffusion-limited current density (4.4 mA cm−2) and electron transfer number (n = 3.8) for three-layered 1D porous carbons are superior to those for random 1D porous carbon. These results demonstrate that layered and core–shell type 1D CMPs and related heteroatom-doped 1D porous carbons can be rationally designed and controlled prepared for high performance energy-related applications.1D conjugated microporous polymers (CMPs) are prepared using a layer-by-layer method, in contrast to one-step random methods. Three-layered CMP has a more favorable inverse decay rate (τeff) than that for random CMP. The as-prepared CMPs are used as precursors to obtain 1D ternary-doped porous carbons. Porous carbon derived from layered CMP exhibits excellent electrocatalytic properties.
      PubDate: 2016-10-04T03:16:31.488255-05:
      DOI: 10.1002/adfm.201603693
  • Development of a Unique Class of Spiro-Type Two-Photon Functional
           Fluorescent Dyes and Their Applications for Sensing and Bioimaging
    • Authors: Hua Chen; Huiming Shang, Yong Liu, Rui Guo, Weiying Lin
      Abstract: Spiro compounds with rigid structures have attracted significant attention in the recent years due to their useful applications in diverse fields such as asymmetric catalysis and organic optoelectronic materials. However, spiro cores have not yet been employed as the spiro-type two-photon fluorescent dyes in the aspects of sensing and bioimaging. Therefore, the spiro-type two-photon fluorescent dyes with excellent two-photon properties are highly sought after. Here, a unique class of spiro-type two-photon fluorescent dyes (STP) is engineered and applied in sensing and bioimaging. The studies indicate that the novel STP fluorescent dyes have favorable two-photon properties from the point view of spiro compounds. By exploiting the superior two-photon optical properties of the STP dyes, the first two-photon ratiometric HOCl fluorescent probe STP-HClO for sensing and imaging HOCl in the living cells and living tissues is constructed, demonstrating the profound value of the new STP dyes for the unprecedented development of the sprio-type fluorescent sensing and imaging agents. It is believed that the innovative STP dyes may pave the way for designing more efficient spiro-type two-photon fluorescent probes and organic optoelectronic materials as well.A unique class of spiro-type two-photon fluorescent dyes (STP) is engineered and applied in sensing and bioimaging for the first time. By exploiting the superior two-photon optical properties of the novel STP dyes, the first two-photon ratiometric HOCl fluorescent probe STP-HClO for sensing and imaging HOCl in living cells and tissues is constructed.
      PubDate: 2016-10-04T03:16:24.56822-05:0
      DOI: 10.1002/adfm.201603495
  • A Multi-Gradient Targeting Drug Delivery System Based on
           RGD-l-TRAIL-Labeled Magnetic Microbubbles for Cancer Theranostics
    • Authors: Lei Duan; Fang Yang, Wen He, Lina Song, Fan Qiu, Ning Xu, Lu Xu, Yu Zhang, Zichun Hua, Ning Gu
      Abstract: The accurately and efficiently targeted delivery of therapeutic/diagnostic agents into tumor areas in a controllable fashion remains a big challenge. Here, a novel cancer targeting magnetic microbubble is elaborately fabricated. First, the γ-Fe2O3 magnetic iron oxide nanoparticles are optimized to chemically conjugate on the surface of polymer microbubbles. Then, arginine-glycine-aspartic acid-l-tumor necrosis factor-related apoptosis-inducing ligand (RGD-l-TRAIL), antitumor targeting fusion protein, is precisely conjugated with magnetic nanoparticles of microbubbles to construct RGD molecularly targeted magnetic microbubble, which is defined as RGD-l-TRAIL@MMBs. Such RGD-l-TRAIL@MMBs is endowed with the multigradient cascade targeting ability following by magnetic targeting, RGD, as well as enhanced permeability and retention effect regulated targeting to result in high cancerous tissue targeting efficiency. Due to the highly specific accumulation of RGD-l-TRAIL@MMBs in the tumor, the accurate diagnostic information of tumor can be obtained by dual ultrasound and magnetic resonance imaging. After imaging, the TRAIL molecules as anticancer agent also get right into the cancer cells by nanoparticle- and RGD-mediated endocytosis to effectively induce the tumor cell apoptosis. Therefore, RGD-l-TRAIL conjugated magnetic microbubbles could be developed as a molecularly targeted multimodality imaging delivery system with the addition of chemotherapeutic cargoes to improve cancer diagnosis and therapy.The optimized arginine-glycine-aspartic acid-l-tumor necrosis factor-related apoptosis-inducing ligand (RGD-l-TRAIL) protein modified novel magnetic microbubble delivery system is endowed with a multigradient cascade targeting strategy followed by magnetic field, RGD, as well as enhanced permeability and retention effect targeting. The results demonstrate highly targeted dual ultrasound and magnetic resonance imaging and targeted TRAIL molecules for tumor selective apoptotic activity.
      PubDate: 2016-10-04T03:10:56.078187-05:
      DOI: 10.1002/adfm.201603637
  • Singlet–Triplet Splitting Energy Management via Acceptor Substitution:
           Complanation Molecular Design for Deep‐Blue Thermally Activated Delayed
           Fluorescence Emitters and Organic Light‐Emitting Diodes Application
    • Authors: Xinyi Cai; Bin Gao, Xiang‐Long Li, Yong Cao, Shi‐Jian Su
      Abstract: A barely reached balance between weak intramolecular‐charge‐transfer (ICT) and small singlet–triplet splitting energy (ΔEST) for reverse intersystem crossing from non‐emissive triplet state to radiative singlet state impedes the realization of deep‐blue thermally activated delayed fluorescence (TADF) materials. By discarding the twisted‐ICT framework for a flattened molecular backbone and introducing a strong acceptor possessing n–π* transition character, hypsochromic color, a large radiative rate (kF), and small ΔEST are achieved simultaneously. Six molecules with a 9,9‐dimethyl‐10‐phenyl‐9,10‐dihydroacridine (i‐DMAc) donor are synthesized and investigated. Coinciding with time‐dependent density functional theory, the reduced dihedral angles between donor (D) and acceptor (A) weaken ICT from dispersed charge density and enable a large kF from increased frontier molecular orbitals overlap. Despite the separated highest occupied (HOMO) and lowest unoccupied molecular orbital (LUMO) population, the intercalation of phenyl bridges between D–A increases kF but significantly lowers the local triplet excited state, indicating small HOMO and LUMO overlap is not a sufficient, but necessary condition for reduced ΔEST. Integrating short conjugation length and carbonyl or triazine acceptors into the complanation molecules, deep‐blue TADF organic light‐emitting diodes demonstrate maximum external quantum efficiencies of 11.5% and 10.9% with Commission Internationale de l'Eclairage coordinates of (0.16, 0.09) and (0.15, 0.11), respectively, which is quite close to the stringent National Television System Committee blue standard.Integrating a strong electron‐withdrawing acceptor moiety with short conjugation length and n–π* character into a planar molecular backbone is promising for meeting high radiative rate, weak intramolecular charge‐transfer state, and small singlet–triplet splitting energy simultaneously. Employing such a strategy, deep‐blue organic light emitting diode with external quantum efficiency of 11.5% and Commission Internationale de l'Eclairage coordinates of (0.16, 0.09) is achieved.
      PubDate: 2016-09-28T06:14:08.873262-05:
      DOI: 10.1002/adfm.201603520
  • Tunable Nanoparticle and Cell Assembly Using Combined Self‐Powered
           Microfluidics and Microcontact Printing
    • Authors: Cyrille Hamon; Malou Henriksen‐Lacey, Andrea La Porta, Melania Rosique, Judith Langer, Leonardo Scarabelli, Ana Belén Serrano Montes, Guillermo González‐Rubio, Marian M. de Pancorbo, Luis M. Liz‐Marzán, Lourdes Basabe‐Desmonts
      Abstract: The combination of cell microenvironment control and real‐time monitoring of cell signaling events can provide key biological information. Through precise multipatterning of gold nanoparticles (GNPs) around cells, sensing and actuating elements can be introduced in the cells' microenviroment, providing a powerful substrate for cell studies. In this work, a combination of techniques are implemented to engineer complex substrates for cell studies. Alternating GNPs and bioactive areas are created with micrometer separation by means of a combination of vacumm soft‐lithography of GNPs and protein microcontract printing. Instead of conventional microfluidics that need syringe pumps to flow liquid in the microchannels, degas driven flow is used to fill dead‐end channels with GNP solutions, rendering the fabrication process straightforward and accessible. This new combined technique is called Printing and Vacuum lithography (PnV lithography). By using different GNPs with various organic coating ligands, different macroscale patterns are obtained, such as wires, supercrystals, and uniformly spread nanoparticle layers that can find different applications depending on the need of the user. The application of the system is tested to pattern a range of mammalian cell lines and obtain readouts on cell viability, cell morphology, and the presence of cell adhesive proteins.Multipatterns of gold nanoparticles and proteins are simultaneously prepared on a large scale using Printing and Vacuum Lithography to direct cell adhesion on a substrate and to control the cell microenvironment by modulating the gold assemblies' properties as well as the cell‐substrate affinity. The application of the system to pattern a range of mammalian cell lines is tested, and readouts on cell viability and cell morphology are obtained.
      PubDate: 2016-09-28T06:14:03.80528-05:0
      DOI: 10.1002/adfm.201602225
  • Codelivery of a π–π Stacked Dual Anticancer Drug Combination with
           Nanocarriers for Overcoming Multidrug Resistance and Tumor Metastasis
    • Authors: Xiao Wei; Yi Wang, Xiang Xiong, Xing Guo, Lei Zhang, Xiaobin Zhang, Shaobing Zhou
      Abstract: The multidrug resistance (MDR) of cancer cells is a major obstacle in cancer chemotherapy and very few strategies are available to overcome it. Here, a new strategy is developed to codeliver a π–π stacked dual anticancer drug combination with an actively targeted, pH‐ and reduction‐sensitive polymer micellar platform for combating multidrug resistance and tumor metastasis. In contrast to other methods, two traditional chemotherapeutics, doxorubicin (DOX) and 10‐hydroxycamptothecin with complex aromatic π–π conjugated structures, are integrated into one drug delivery system via a π–π stacking interaction, which enables the released drugs to evade the recognition of drug pumps due to a slight change in the drug's molecular structure. The micelles exhibit active targeting of DOX‐resistant human breast cancer MCF‐7 cells (MCF‐7/ADR) and have the ability to control the release of the drug in response to the microenvironmental stimuli of tumor cells. As a result, the codelivery of the π–π stacked dual anticancer drug combination displays high therapeutic efficacy in the MCF‐7/ADR tumor model and successfully prevents the lung metastasis of tumor cells. The mechanism underlying the reversal of MDR is investigated, and the results reveal that the synergistic effect of the π–π stacked dual drugs promotes mitochondria‐dependent apoptosis.A π–π stacked dual anticancer drug combination is successfully delivered into target cells with an actively targeted, pH‐ and reduction‐sensitive nanocarrier. The π–π stacking interaction enables the released therapeutic agents to evade the recognition of drug pumps and has a great capacity for overcoming multidrug resistance and tumor metastasis.
      PubDate: 2016-09-28T06:13:49.788531-05:
      DOI: 10.1002/adfm.201603336
  • Size‐Selective Binding of Sodium and Potassium Ions in Nanoporous Thin
           Films of Polymerized Liquid Crystals
    • Authors: Gerardus M. Bögels; Jody A. M. Lugger, Olga J. G. M. Goor, Rint P. Sijbesma
      Abstract: The development of a nanoporous material from a columnar liquid crystalline complex between a polymerizable benzoic acid derivative and a 1,3,5‐tris(1H‐benzo[d]imidazol‐2‐yl)benzene template molecule is described. The morphology of the liquid crystalline complex is retained upon polymerization and quantitative removal of the template molecule affords a nanoporous material with the same lattice parameters. The nanoporous material selectively binds cations from aqueous solution, with selectivity for sodium and potassium ions over lithium and barium ions, as shown with FT‐IR. Binding is also quantified gravimetrically with a quartz crystal microbalance with dissipation monitoring, a technique that is used for this purpose for the first time here.A nanoporous material was developed by the self‐assembly and cross‐linking of a hydrogen‐bonded columnar liquid crystalline complex. Subsequent quantitative removal of the template affords the nanoporous material that size‐selectively binds sodium and potassium ions over other ions. This is analyzed for the first time by utilizing the quartz crystal microbalance.
      PubDate: 2016-09-28T06:13:41.130547-05:
      DOI: 10.1002/adfm.201603408
  • All‐in‐One Theranostic Nanoplatform Based on Hollow TaOx for
           Chelator‐Free Labeling Imaging, Drug Delivery, and Synergistically
           Enhanced Radiotherapy
    • Authors: Guosheng Song; Yu Chao, Yuyan Chen, Chao Liang, Xuan Yi, Guangbao Yang, Kai Yang, Liang Cheng, Qiao Zhang, Zhuang Liu
      Abstract: Despite extensive use of radiotherapy in cancer treatment, there has been huge demand to improve its efficacy and accuracy in tumor destruction. To this end, nanoparticle‐based radiosensitizers, particularly those with high‐Z elements, have been explored to enhance radiotherapy. Meanwhile, imaging is an essential tool prior to the individual planning of precise radiotherapy. Here, hollow tantalum oxide (H‐TaOx) nanoshells are prepared using a one‐pot template‐free method and then modified with polyethylene glycol (PEG), yielding H‐TaOx‐PEG nanoshells for imaging‐guided synergistically enhanced radiotherapy. H‐TaOx‐PEG nanoshells show strong intrinsic binding with metal ions such as Fe3+ and 99mTc4+ upon simple mixing, enabling magnetic resonance imaging and single photon emission computed tomography imaging, respectively, which are able to track in vivo distribution of those nanoshells and locate the tumor. With mesoporous shells and large cavities, those H‐TaOx‐PEG nanoshells show efficient loading of 7‐ethyl‐10‐hydroxycamptothecin (SN‐38), a hydrophobic chemotherapeutic drug. By means of the radiosensitization effect of Ta to deposit X‐ray energy inside tumors, as well as SN‐38‐induced cell cycle arrest into radiation‐sensitive phases, H‐TaOx‐PEG@SN‐38 can offer remarkable synergistic therapeutic outcome in the combined chemoradiotherapy. Without appreciable systemic toxicity, such hollow‐TaOx nanostructure may therefore find promising applications in multimodal imaging and enhanced cancer radiotherapy.Hollow TaOx nanoshells are fabricated via a rather simple one‐pot template‐free method. The nanoshells can bond with metal ions in the absence of molecular chelators, enabling magnetic resonance imaging (with Fe3+) and nuclear imaging (e.g., with 99mTc4+). Meanwhile, TaOx nanoshells can efficiently load hydrophobic drugs to realize chemoradiotherapy, which results in great synergistic antitumor therapeutic outcomes via a comprehensive mechanism.
      PubDate: 2016-09-28T06:05:48.472155-05:
      DOI: 10.1002/adfm.201603845
  • Ternary Ta2NiSe5 Flakes for a High‐Performance Infrared
    • Authors: Liang Li; Weike Wang, Lin Gan, Nan Zhou, Xiangde Zhu, Qi Zhang, Huiqiao Li, Mingliang Tian, Tianyou Zhai
      Abstract: Multielemental systems enable the use of multiple degrees of freedom for control of physical properties by means of stoichiometric variation. This has attracted extremely high interest in the field of 2D optoelectronics in recent years. Here, for the first time, multilayer 2D ternary Ta2NiSe5 flakes are successfully fabricated using a mechanical exfoliation method from chemical vapor transport synthesized high quality bulk and the optoelectronic properties are systematically investigated. Importantly, a high responsivity of 17.21 A W−1 and high external quantum efficiency of 2645% are recorded from an as‐fabricated photodetector at room temperature in air; this is superior to most other 2D materials‐based photodetectors that have been reported. More intriguingly, a usual sublinear and an unusual superlinear light‐intensity‐dependent photocurrent are observed under air and vacuum, respectively. These excellent and special properties make multilayer ternary Ta2NiSe5 a highly competitive candidate for future infrared optoelectronic applications and an interesting platform for photophysics studies.A multilayered ternary single crystal of Ta2NiSe5 is proposed to serve as an infrared photodetector for the first time. The photodetector displays a high responsivity of 17.21 A W−1 at room temperature. Such high performance makes it a promising candidate for future optoelectronic applications.
      PubDate: 2016-09-28T06:05:35.730057-05:
      DOI: 10.1002/adfm.201603804
  • Anomalous Enhancement of Li‐O2 Battery Performance with Li2O2 Films
           Assisted by NiFeOx Nanofiber Catalysts: Insights into Morphology Control
    • Authors: Jiaqiang Huang; Biao Zhang, Zhaowen Bai, Ruiqiang Guo, Zheng‐Long Xu, Zoya Sadighi, Lei Qin, Tong‐Yi Zhang, Guohua Chen, Baoling Huang, Jang‐Kyo Kim
      Abstract: It is generally understood that particle‐shaped Li2O2 is preferred in Li‐O2 batteries (LOBs) because the dominance of Li2O2 films may lead to poor electrochemical performance. The influence of Li2O2 morphology and its nucleation mechanism are probed by experiments along with the first‐principle calculations. It is revealed that the LOBs with Li2O2 films deliver unexpectedly improved capacities, longer cycles, and significantly reduced overpotentials assisted by NiFeOx nanofiber catalysts. The energetically favored Li 2a vacancies under LiO2‐rich conditions, small crystallites, and large contact areas with the electrode/electrolyte explain the anomalous performance enhancement. Li2O2 films are formed by a heterogeneous nucleation mechanism and the voltage applied, electrolyte, electrode surface, and use of catalysts are identified as the parameters controlling the mechanisms. The mapped correlations among these parameters shed light on the control of Li2O2 morphology for developing high‐performance LOBs.The film‐shaped discharge product, Li2O2, has long been considered detrimental for Li‐O2 batteries because it may lead to premature cell death. Contrary to this, it is revealed that the Li2O2 films ameliorate the battery's electrochemical performance when assisted by NiFeOx catalysts. The presence of Li vacancies, small size crystallites, and large contact areas with the electrode/electrolyte provides solid evidence of this finding.
      PubDate: 2016-09-27T06:37:14.47939-05:0
      DOI: 10.1002/adfm.201603178
  • Novel Cathode Materials for Na‐Ion Batteries Composed of Spoke‐Like
           Nanorods of Na[Ni0.61Co0.12Mn0.27]O2 Assembled in Spherical Secondary
    • Authors: Jang‐Yeon Hwang; Seung‐Taek Myung, Chong Seung Yoon, Sung‐Soo Kim, Doron Aurbach, Yang‐Kook Sun
      Abstract: The development of high‐energy and high‐power density sodium‐ion batteries is a great challenge for modern electrochemistry. The main hurdle to wide acceptance of sodium‐ion batteries lies in identifying and developing suitable new electrode materials. This study presents a composition‐graded cathode with average composition Na[Ni0.61Co0.12Mn0.27]O2, which exhibits excellent performance and stability. In addition to the concentration gradients of the transition metal ions, the cathode is composed of spoke‐like nanorods assembled into a spherical superstructure. Individual nanorod particles also possess strong crystallographic texture with respect to the center of the spherical particle. Such morphology allows the spoke‐like nanorods to assemble into a compact structure that minimizes its porosity and maximizes its mechanical strength while facilitating Na+‐ion transport into the particle interior. Microcompression tests have explicitly verified the mechanical robustness of the composition‐graded cathode and single particle electrochemical measurements have demonstrated the electrochemical stability during Na+‐ion insertion and extraction at high rates. These structural and morphological features contribute to the delivery of high discharge capacities of 160 mAh (g oxide)−1 at 15 mA g−1 (0.1 C rate) and 130 mAh g−1 at 1500 mA g−1 (10 C rate). The work is a pronounced step forward in the development of new Na ion insertion cathodes with a concentration gradient.The tailored microstructural design of spoke‐like nanorods assemblies and their unique chemical composition contribute to high capacity, excellent rate capability, and low temperature performance due to their superior mechanical strength during Na+ ion insertion and extraction even at high rates. Furthermore, this unique particle morphology guarantees high thermal stability in the desodiated state of electrodes materials.
      PubDate: 2016-09-27T06:30:53.437903-05:
      DOI: 10.1002/adfm.201603439
  • On Optical Dipole Moment and Radiative Recombination Lifetime of Excitons
           in WSe2
    • Authors: Chenhao Jin; Jonghwan Kim, Kedi Wu, Bin Chen, Edward S. Barnard, Joonki Suh, Zhiwen Shi, Steven G. Drapcho, Junqiao Wu, Peter James Schuck, Sefaattin Tongay, Feng Wang
      Abstract: Optical dipole moment is the key parameter of optical transitions, as it directly determines the strength of light–matter interaction such as intrinsic radiative lifetime. However, experimental determination of these fundamental properties of excitons in monolayer WSe2 is largely limited, because the commonly used measurement, such as (time‐resolved) photoluminescence, is inherently difficult to probe the intrinsic properties. For example, dark states below bright exciton can change the photoluminescence emission rate by orders of magnitude and gives an “effective” radiative lifetime distinctive from the intrinsic one. On the other hand, such “effective” radiative lifetime becomes important itself because it describes how dark states affect exciton dynamics. Unfortunately, the “effective” radiative lifetime in monolayer WSe2 is also not determined as it requires photoluminescence measurement with resonant excitation, which is technically difficult. These difficulties are overcome here to obtain both the “intrinsic” and “effective” radiative lifetime experimentally. A framework is developed to determine the dipole moment and “intrinsic” radiative lifetime of delocalized excitons in monolayer WSe2 from the absorption measurements. In addition, the “effective” radiative lifetime in WSe2 is obtained through time‐resolved photoluminescence and absolute quantum‐yield measurement at resonant excitation. These results provide helpful information for fundamental understanding of exciton light–matter interaction in WSe2.The dipole moment and “intrinsic” radiative lifetime of excitons in WSe2 are determined from absorption measurements. The “effective” radiative lifetime of excitons is also obtained using time‐resolved photoluminescence and absolute quantum yield measurements with resonant excitation. The framework developed provides helpful information to determine fundamental quantities of exciton light–matter interaction, and to understand the dynamics of delocalized excitons in solids.
      PubDate: 2016-09-27T05:02:13.590594-05:
      DOI: 10.1002/adfm.201601741
  • Immune Complexes Mimicking Synthetic Vaccine Nanoparticles for Enhanced
           Migration and Cross‐Presentation of Dendritic Cells
    • Authors: Sun‐Young Kim; Hathaichanok Phuengkham, Young‐Woock Noh, Hong‐Guen Lee, Soong Ho Um, Yong Taik Lim
      Abstract: The well‐designed activation of dendritic cells (DCs) by enhancing the delivery of antigens and immunostimulatory adjuvants into DCs is a key strategy for efficient cancer immunotherapy. Antigen‐antibody immune complexes (ICs) are known to directly bind to and cross‐link Fc‐gamma receptors (FcγRs) on DCs, which induce enhanced migration of DCs to draining lymph nodes through the up‐regulation of the chemokine receptor CCR7 and cross‐presentation inducing cytotoxic T lymphocyte (CTL) response against tumor antigen. In this study, ICs mimicking synthetic vaccine nanoparticles (NPs) are designed and synthesized by the coating of poly (lactic‐co‐glycolic acid) (PLGA) NPs containing adjuvant (CpG oligodeoxynuleotides (ODNs) as toll‐like receptor 9 ligands) with ovalbumin (OVA) proteins (as model antigens) and by the formation of OVA–OVA antibody ICs. Through the combination of FcγRs‐mediated efficient antigen uptake and CpG ODNs‐based immunostimulation, the secretion of TNF‐α (12.3‐fold), IL‐6 (7.29‐fold), and IL‐12 (11‐fold), homing ability to lymph nodes (7.5‐fold), and cross‐presentation (83.8‐fold IL‐2 secretion) are dramatically increased in DCs treated with PLGA(IC/CpG) NPs. Furthermore, mice vaccinated with DCs treated with PLGA(IC/CpG) NPs induced significant tumor (EG7‐OVA) growth inhibition as well as prolonged survival through CTL‐mediated enhanced cytotoxicity, antigen‐specific responses, and IFN‐γ secretion.Antigen‐antibody immune complexes (ICs) mimicking synthetic vaccine nanoparticles for activation of dendritic cells for antigen‐specific adaptive immunity are designed. Mice immunized with dendritic cells treated with ICs mimicking synthetic vaccine nanoparticles induce significant tumor growth inhibition as well as prolonged survival through cytotoxic T lymphocyte response.
      PubDate: 2016-09-27T01:24:21.244862-05:
      DOI: 10.1002/adfm.201603651
  • Electrochemical Intercalation of Potassium into Graphite
    • Authors: Jin Zhao; Xiaoxi Zou, Yujie Zhu, Yunhua Xu, Chunsheng Wang
      Abstract: Exceptional cycling performance of graphite anode in K‐ion batteries is demonstrated with a reversible capacity of 246 mAh g–1 and 89% retention of the initial capacity after 200 cycles. Although the graphite anode experiences huge volume change and worse kinetics during K intercalation/deintercalation, the cycling stability delivered in K‐ion batteries is comparable to that of Li‐ion batteries using the same graphite anode. The combination of excellent electrochemical performance, the abundance and wide availability of K in earth's crust, and the well‐developed technology of the graphite anode make the K‐ion battery very attractive for offering a low cost battery chemistry for large‐scale energy storage applications.Stable potassium‐ion batteries using graphite anodes with reversible capacity of 246 mAh g–1 and 89% remains after 200 cycles are demonstrated. In spite of worse kinetics and much larger volume change for K than Li, comparable cycling stability is achieved. This provides a battery chemistry that is compatible with commercial Li‐ion batteries using abundant potassium, thus promising low cost for large‐scale energy storage.
      PubDate: 2016-09-26T08:46:39.853069-05:
      DOI: 10.1002/adfm.201602248
  • Synergistic Effect of PbI2 Passivation and Chlorine Inclusion Yielding
           High Open‐Circuit Voltage Exceeding 1.15 V in Both Mesoscopic and
           Inverted Planar CH3NH3PbI3(Cl)‐Based Perovskite Solar Cells
    • Authors: Fangyuan Jiang; Yaoguang Rong, Huawei Liu, Tiefeng Liu, Lin Mao, Wei Meng, Fei Qin, Youyu Jiang, Bangwu Luo, Sixing Xiong, Jinhui Tong, Yun Liu, Zaifang Li, Hongwei Han, Yinhua Zhou
      Abstract: Enhancing open‐circuit voltage in CH3NH3PbI3(Cl) perovskite solar cells has become a major challenge for approaching the theoretical limit of the power conversion efficiency. Here, for the first time, it is demonstrated that the synergistic effect of PbI2 passivation and chlorine incorporation via controlling the molar ratio of PbI2, PbCl2 (or MACl), and MAI in the precursor solutions, boosts the open‐circuit voltage of CH3NH3PbI3(Cl) perovskite solar cells over 1.15 V in both mesoscopic and inverted planar perovskite solar cells. Such high open‐circuit voltage can be attributed to the enhanced photoluminescence emission and carrier lifetime associated with the reduced trap densities. The morphology and composition analysis using scanning electron microscopy, X‐ray diffraction measurements, and energy dispersive X‐ray spectroscopy confirm the high quality of the optimized CH3NH3PbI3(Cl) perovskite film. On this basis, record‐high efficiencies of 16.6% for nonmetal‐electrode all‐solution‐processed perovskite solar cells and 18.4% for inverted planar perovskite solar cells are achieved.A synergistic effect of PbI2 passivation and chlorine incorporation induces suppression of non‐radiative recombination in a perovskite film. This leads to a high open‐circuit voltage exceeding 1.15 V in both mesoscopic and inverted planar CH3NH3PbI3(Cl)‐based perovskite solar cells.
      PubDate: 2016-09-26T08:31:21.929891-05:
      DOI: 10.1002/adfm.201603968
  • Single‐Layer MoS2 Nanosheets with Amplified Photoacoustic Effect for
           Highly Sensitive Photoacoustic Imaging of Orthotopic Brain Tumors
    • Authors: Jingqin Chen; Chengbo Liu, Dehong Hu, Feng Wang, Haiwei Wu, Xiaojing Gong, Xin Liu, Liang Song, Zonghai Sheng, Hairong Zheng
      Abstract: Photoacoustic (PA) imaging, as a fast growing technology that combines the high contrast of light and large penetration depth of ultrasound, has demonstrated great potential for molecular imaging of cancer. However, PA molecular imaging of orthotopic brain tumors is still challenging, partially due to the limited options and insufficient sensitivity of available PA molecular probes. Here, the direct formation of single‐layer (S‐MoS2), few‐layer (F‐MoS2), and multi‐layer (M‐MoS2) nanosheets by the albumin‐assisted exfoliation without further surface modifications is reported. It is demonstrated that the PA effect of the MoS2 nanosheets is highly dependent on their layered nanostructures. Decreasing the number of nanosheet layers from M‐MoS2 to S‐MoS2 can both significantly enhance the near‐infrared light absorption and improve the elastic properties of the nanomaterial, resulting in greatly amplified PA effect. The in vitro experiments demonstrate that the prepared S‐MoS2 with excellent biocompatibility can be efficiently internalized into U87 glioma cells, producing strong PA signals for highly sensitive detection of brain tumor cells, with a detection limit of ≈100 cells. Intravenous administration of S‐MoS2 to both U87 subcutaneous and orthotopic tumor‐bearing mice shows highly efficient tumor retention and significantly enhanced PA contrast. Tumor tissue ≈1.5 mm below the skull can still be clearly visualized in vivo. Previous studies suggest that the fabricated S‐MoS2 with amplified PA effect have high potential to serve as an efficient nanoplatform for sensitive PA molecular imaging and hold promising prospect for translational medicine.Single‐layer MoS2 nanosheets with an amplified photoacoustic (PA) effect are demonstrated and applied for highly sensitive PA molecular imaging of brain tumors in both subcutaneous and orthotopic mouse models. They demonstrate very efficient tumor retention and enhanced contrast performance. The novel PA probe has great potential for PA‐imaging‐guided cancer therapy and theranostic applications.
      PubDate: 2016-09-26T08:31:17.621718-05:
      DOI: 10.1002/adfm.201603758
  • Hyperspectral Imaging Offers Visual and Quantitative Evidence of Drug
           Release from Zwitterionic‐Phospholipid‐Nanocarbon When Concurrently
           Tracked in 3D Intracellular Space
    • Authors: Santosh K. Misra; Fatemeh Ostadhossein, Enrique Daza, Elyse V. Johnson, Dipanjan Pan
      Abstract: Spatial and spectral information of a nanocarrier and its payload is crucial for the advancement of luminescence‐based imaging, disease detection, and treatment in complex biological environment. However, it remains challenging to track and quantify the delivery and localization of drugs lacking inherent fluorescence. It is demonstrated that sub 30 nm phospholipid‐stabilized nanoparticles can be detected and quantified using hyperspectral transmitted light microscopy without using a fluorophore. In two proposed model systems, phospholipid‐passivated carbon nanoparticles incorporate the drug in either free form or as a lipid‐based prodrug. Following a rigorous characterization of these nanoparticles, in vitro toxicities via loss in cell growth density and mitochondrial respiration is studied in MCF‐7 breast cancer cells. Furthermore, a detailed inhibitor based study reveals that these particles are internalized based on a clathrin‐mediated pathway, irrespective of the choice of drug formulation. Hyperspectral imaging is performed to obtain the colocalization of carbon nanoparticles and drug molecules intracellularly and can successfully be tracked while therapeutic release is quantified in 3D space. The present work demonstrates that nanoparticles and therapeutic agents can be mapped and measured simultaneously barring the requirement of a dye, thus providing new avenues in the spatiotemporal characterization and synchronous detection and quantification of payload and carrier.Hyperspectral mapping of drug‐laden phospholipid‐nanocarbon offers visual clue of release of drug in vitro and synchronous tracking of nanoformulation in 3D intracellular space.
      PubDate: 2016-09-26T08:31:11.262195-05:
      DOI: 10.1002/adfm.201602966
  • Unprecedented “All‐in‐One” Lanthanide‐Doped Mesoporous Silica
           Frameworks for Fluorescence/MR Imaging and Combination of NIR Light
           Triggered Chemo‐Photodynamic Therapy of Tumors
    • Authors: Poliraju Kalluru; Raviraj Vankayala, Chi‐Shiun Chiang, Kuo Chu Hwang
      Abstract: Designing a single multifunctional nanoparticle that can simultaneously impart both diagnostic and therapeutic functions is considered to be a long‐lasting hurdle for biomedical researchers. Conventionally, a multifunctional nanoparticle can be constructed by integrating organic dyes/magnetic nanoparticles to impart diagnostic functions and anticancer drugs/photosensitizers to achieve therapeutic outcomes. These multicomponents systems usually suffer from severe photobleaching problems and cannot be activated by near‐infrared (NIR) light. Here, it is demonstrated that all‐in‐one lanthanide‐doped mesoporous silica frameworks (EuGdOx@MSF) loaded with an anticancer drug, doxorubicin (DOX) can facilitate simultaneous bimodal magnetic resonance (MR) imaging with approximately twofold higher T1‐MR contrast as compared to the commercial Gd(III)‐DTPA complex and fluorescence imaging with excellent photostability. Upon a very low dose (130 mW cm−2) of NIR light (980 nm) irradiation, the EuGdOx@MSF not only can sensitize formation of singlet oxygen (1O2) by itself but also can phototrigger the release of the DOX payload effectively to exert combined chemo‐photodynamic therapeutic (PDT) effects and destroy solid tumors in mice completely. It is also discovered for the first time that the EuGdOx@MSF‐mediated PDT effect can suppress the level of the key drug resistant protein, i.e., p‐glycoprotein (p‐gp) and help alleviate the drug resistant problem commonly associated with many cancers.Unprecedented all‐in‐one multifunctional lanthanide‐doped mesoporous silica frameworks (EuGdOx@MSF) are used for bimodal fluorescence/T1‐magnetic resonance (MR) imaging and near infrared (NIR) light‐triggered chemo‐photodynamic therapy to completely destroy tumors. It is demonstrated that EuGdOx@MSF can sensitize formation of singlet oxygen upon NIR light excitation and exert nanomaterial‐mediated photodynamic therapy effects without the need for externally added organic photosensitizers.
      PubDate: 2016-09-26T08:30:59.170307-05:
      DOI: 10.1002/adfm.201603749
  • Nanodroplets for Stretchable Superconducting Circuits
    • Authors: Long Ren; Jincheng Zhuang, Gilberto Casillas, Haifeng Feng, Yuqing Liu, Xun Xu, Yundan Liu, Jun Chen, Yi Du, Lei Jiang, Shi Xue Dou
      Abstract: The prospective utilization of nanoscale superconductors as micro/nanocoils or circuits with superior current density and no electrical resistance loss in next‐generation electronics or electromagnetic equipment represents a fascinating opportunity for new microsystem technologies. Here, a family of superconducting liquid metals (Ga–In–Sn alloys) and their nanodroplets toward printable and stretchable superconducting micro/nanoelectronics is developed. By tuning the composition of liquid metals the highest superconducting critical temperature (Tc) in this family can be modulated and achieved as high as 6.6 K. The liquid metal nanodroplets retain their bulk superconducting properties and can be easily dispersed in different solvents as inks. The printable and stretchable superconducting micro/nano coils, circuits and electrodes have been fabricated by inkjet printer or laser etching by using superconducting nanodroplets inks. This novel superconducting system greatly promotes the commercial utilization of superconductors into advanced flexible micro/nanoelectronic devices and offers a new platform for developing more application with superconductors.Superconducting eutectic gallium–indium–tin (EGaInSn) alloys and their nanosized droplets with different weight ratios are developed for realizing printable and stretchable superconducting circuits. The highest superconducting critical temperature of EGaInSn is 6.6 K. The corresponding EGaInSn nanodroplets retain the bulk superconducting properties. Their dispersion in various solvents shows excellent wettability, which can be easily applied to print stretchable superconductive micro/nanoelectronics.
      PubDate: 2016-09-26T08:30:49.94031-05:0
      DOI: 10.1002/adfm.201603427
  • Size Effects of Platinum Nanoparticles in the Photocatalytic Hydrogen
           Production Over 3D Mesoporous Networks of CdS and Pt Nanojunctions
    • Authors: Ioannis Vamvasakis; Bin Liu, Gerasimos S. Armatas
      Abstract: Catalysts for the photogeneration of hydrogen from water are key for realizing solar energy conversion. Despite tremendous efforts, developing hydrogen evolution catalysts with high activity and long‐term stability remains a daunting challenge. Herein, the design and fabrication of mesoporous Pt‐decorated CdS nanocrystal assemblies (NCAs) are reported, and their excellent performance for the photocatalytic hydrogen production is demonstrated. These materials comprise varying particle size of Pt (ranging from 1.8 to 3.3 nm) and exhibit 3D nanoscale pore structure within the assembled network. Photocatalytic measurements coupled with UV–vis/NIR optical absorption, photoluminescence, and electrochemical impedance spectroscopy studies suggest that the performance enhancement of these catalytic systems arises from the efficient hole transport at the CdS/electrolyte interface and interparticle Pt/CdS electron‐transfer process as a result of the deposition of Pt. It is found that the Pt‐CdS NCAs catalyst at 5 wt% Pt loading content exerts a 1.2 mmol h−1 H2‐evolution rate under visible‐light irradiation (λ ≥ 420 nm) with an apparent quantum yield of over 70% at wavelength λ = 420 nm in alkaline solution (5 m NaOH), using ethanol (10% v/v) as sacrificial agent. This activity far exceeds those of the single CdS and binary noble metal/CdS systems, demonstrating the potential for practical photocatalytic hydrogen production.3D mesoporous architectures of CdS and Pt nanocrystals are demonstrated as highly effective catalysts for the hydrogen evolution reaction (HER). Photocatalytic measurements coupled with spectroscopic studies suggest that deposition of ultrasmall Pt nanoparticles enhances the HER activity because of variations in the band‐edge positions and electron donor density of CdS nanocrystals.
      PubDate: 2016-09-26T08:30:43.149252-05:
      DOI: 10.1002/adfm.201603292
  • High Performance, Multiplexed Lung Cancer Biomarker Detection on a
           Plasmonic Gold Chip
    • Authors: Bin Liu; Yaling Li, Hao Wan, Lin Wang, Wei Xu, Shoujun Zhu, Yongye Liang, Bo Zhang, Jiatao Lou, Hongjie Dai, Kun Qian
      Abstract: Diagnosis of lung cancer is performed using a plasmonic gold (pGOLD) chip through multiplexed near‐infrared (NIR) detection of carcino‐embryonic antigen (CEA), Cyfra21‐1, and neuron‐specific enolase (NSE) in the serum samples of patients. With ≈50‐fold enhancement of NIR fluorescence, multiplexed microarray analysis of CEA, Cyfra21‐1, and NSE in 10 μL of human serum or whole blood samples on pGOLD chip leads to markedly improved limit‐of‐quantification, limit‐of‐detection, reproducibility, and higher diagnostic sensitivity and specificity compared to traditional biochips and Luminex technology currently in use in hospitals.Plasmonic gold (pGOLD) chip‐based diagnosis of lung cancer is performed using multiplexed near‐infrared detection of biomarkers in the serum samples of patients. Multiplexed microarray analysis of biomarkers in 10 μL of human serum on a pGOLD chip leads to markedly improved limit‐of‐quantification, limit‐of‐detection, reproducibility, and higher diagnostic sensitivity and specificity compared to traditional biochips and Luminex technology currently in use in hospitals.
      PubDate: 2016-09-26T08:30:38.800978-05:
      DOI: 10.1002/adfm.201603547
  • Effective Ligand Engineering of the Cu2ZnSnS4 Nanocrystal Surface for
           Increasing Hole Transport Efficiency in Perovskite Solar Cells
    • Authors: Laraib Sarfraz Khanzada; Ievgen Levchuk, Yi Hou, Hamed Azimi, Andres Osvet, Rameez Ahmad, Marco Brandl, Patrick Herre, Monica Distaso, Rainer Hock, Wolfgang Peukert, Miroslaw Batentschuk, Christoph J. Brabec
      Abstract: Effective engineering of surface ligands in semiconductor nanocrystals can facilitate the electronic interaction between the individual nanocrystals, making them promising for low‐cost optoelectronic applications. Here, the use of high purity Cu2ZnSnS4 (CZTS) nanocrystals as the photoactive layer and hole‐transporting material is reported in low‐temperature solution‐processed solar cells. The high purity CZTS nanocrystals are prepared by engineering the surface ligands of CZTS nanocrystals, capped originally with the long‐chain organic ligand oleylamine. After ligand removal, CZTS nanocrystals show substantial improvement in photoconductivity and mobility, displaying also an appreciable photoresponse in a simple heterojunction solar cell architecture. More notably, CZTS nanocrystals exhibit excellent hole‐transporting properties as interface layer in perovskite solar cells, yielding power conversion efficiency (PCE) of 15.4% with excellent fill factor (FF) of 81%. These findings underscore the importance of removing undesired surface ligands in nanocrystalline optoelectronic devices, and demonstrate the great potential of CZTS nanocrystals as both active and passive material for the realization of low‐cost efficient solar cells.Effective ligand engineering of Cu2ZnSnS4 (CZTS) nanocrystal surface is demonstrated to lead to improvement of the electrical properties of the thin film. Furthermore, surface‐modified CZTS nanocrystals exhibit excellent hole transporting properties as the interface layer in a perovskite solar cell. The perfomance of perovskite devices is shown to vary from 12.2% to 15.4% as a function of ligand removal.
      PubDate: 2016-09-26T08:30:34.779617-05:
      DOI: 10.1002/adfm.201603441
  • Invisibility Dips of Near‐Field Energy Transport in a Spoof
           Plasmonic Metadimer
    • Authors: Fei Gao; Zhen Gao, Yu Luo, Baile Zhang
      Abstract: Invisibility dips, i.e., minima in scattering spectrum associated with asymmetric Fano‐like line‐shapes, have been predicted with transformation optics in studying strong coupling between two plasmonic nanoparticles. This feature of strongly coupled plasmonic nanoparticles holds promise for sensor cloaking. It requires an extremely narrow gap between the two nanoparticles, preventing its experimental observation at optical frequencies. Here, the concept of spoof surface plasmons is used to facilitate the strong coupling between two spoof‐localized‐surface‐plasmon (SLSP) resonators. Instead of observing in far field, the near‐field energy transport is probed through the two SLSP resonators. By virtue of enhanced coupling between the two resonators stacked vertically, a spectral transmission dip with asymmetric Fano‐like line‐shape, similar to the far‐field “invisibility dips” predicted by transformation optics, is observed. The underlying mode interference mechanism is further demonstrated by directly imaging the field maps of interfered waves that are tightly localized around the resonators. These near‐field “invisibility dips” may find use in near‐field sensing, on‐chip switching, filters, and logical operation elements.Invisibility dips associated with asymmetric line‐shapes, arising from interference between multipolar modes, are observed in a spoof‐localized‐surface‐plasmon dimer. The sensing capability of invisibility dips is also demonstrated.
      PubDate: 2016-09-26T07:40:29.663122-05:
      DOI: 10.1002/adfm.201602233
  • Band Diagram and Rate Analysis of Thin Film Spinel LiMn2O4 Formed by
           Electrochemical Conversion of ALD‐Grown MnO
    • Authors: Matthias J. Young; Hans‐Dieter Schnabel, Aaron M. Holder, Steven M. George, Charles B. Musgrave
      Abstract: Nanoscale spinel lithium manganese oxide is of interest as a high‐rate cathode material for advanced battery technologies among other electrochemical applications. In this work, the synthesis of ultrathin films of spinel lithium manganese oxide (LiMn2O4) between 20 and 200 nm in thickness by room‐temperature electrochemical conversion of MnO grown by atomic layer deposition (ALD) is demonstrated. The charge storage properties of LiMn2O4 thin films in electrolytes containing Li+, Na+, K+, and Mg2+ are investigated. A unified electrochemical band‐diagram (UEB) analysis of LiMn2O4 informed by screened hybrid density functional theory calculations is also employed to expand on existing understanding of the underpinnings of charge storage and stability in LiMn2O4. It is shown that the incorporation of Li+ or other cations into the host manganese dioxide spinel structure (λ‐MnO2) stabilizes electronic states from the conduction band which align with the known redox potentials of LiMn2O4. Furthermore, the cyclic voltammetry experiments demonstrate that up to 30% of the capacity of LiMn2O4 arises from bulk electronic charge‐switching which does not require compensating cation mass transport. The hybrid ALD‐electrochemical synthesis, UEB analysis, and unique charge storage mechanism described here provide a fundamental framework to guide the development of future nanoscale electrode materials for ion‐incorporation charge storage.Three key advances are described in this work: 1) Room‐temperature electrochemical conversion of MnO to LiMn2O4 demonstrates phase‐controlled electrochemical synthesis of metastable cation intercalation polymorphs. 2) The new unified electrochemical band diagram approach enables prediction of LiMn2O4 redox potentials, motivating its use to study battery materials. 3) Experimental verification of bulk capacitive charge storage inspires materials design to exploit this effect for rapid energy storage.
      PubDate: 2016-09-22T06:25:45.733899-05:
      DOI: 10.1002/adfm.201602773
  • Ultrabroadband Optical Superchirality in a 3D Stacked‐Patch Plasmonic
           Metamaterial Designed by Two‐Step Glancing Angle Deposition
    • Authors: Yidong Hou; Ho Ming Leung, Che Ting Chan, Jinglei Du, Helen Lai‐Wai Chan, Dang Yuan Lei
      Abstract: Low‐cost and large‐scale fabrication of 3D chiral metamaterials is highly desired for potential applications such as nanophotonics devices and chiral biosensors. One of the promising fabrication methods is to use glancing angle deposition (GLAD) of metal on self‐assembled dielectric microsphere array. However, structural handedness varies locally due to long‐range disorder of the array and therefore large‐scale realization of the same handedness is impossible. Here, using symmetry considerations a two‐step GLAD process is proposed to eliminate this longstanding problem. In the proposed scheme, the unavoidable long‐range disorder gives rise to microscale domains of the same handedness but of slightly different structural geometries and ultimately contributes to a broad‐band response. Experimentally, a record‐breaking superchiral response of circular dichroism signal of ≈11° is demonstrated and an average polarization rotation angle of 27° in the visible region on ≈1 cm2 sample is observed. Computer‐aided geometric reconstruction with experimental parameters unambiguously reveal the presence of strong structural anisotropy and chirality in the prepared stacked‐patch plasmonic chiral metamaterial; microscopic spectral analyses combined with full‐wave electromagnetic simulations coherently provide deeper insights into the measured circular dichroism and optical activity. The observed chiroptical response can also be flexibly controlled by adjusting the deposition parameters for various potential applications.A 3D stacked‐patch plasmonic metamaterial is fabricated and it shows a circular dichroism signal of ≈11° and an average polarization rotation angle of 27° in a wide spectral range from 480 to 750 nm. This giant ultrabroadband chiroptical response results from a constructively weighted average of local chiralities and concurrent elimination of the racemic mixture in the sample.
      PubDate: 2016-09-22T06:21:00.273316-05:
      DOI: 10.1002/adfm.201602800
  • Epidermal Supercapacitor with High Performance
    • Authors: Pingshan Luan; Nan Zhang, Weiya Zhou, Zhiqiang Niu, Qiang Zhang, Le Cai, Xiao Zhang, Feng Yang, Qingxia Fan, Wenbin Zhou, Zhuojian Xiao, Xiaogang Gu, Huiliang Chen, Kewei Li, Shiqi Xiao, Yanchun Wang, Huaping Liu, Sishen Xie
      Abstract: Recent development in epidermal and bionic electronics systems has promoted the increasing demand for supercapcacitors with micrometer‐thickness and good compatibility. Here, a highly flexible free‐standing epidermal supercapacitor (SC‐E) with merely 1 μm thickness and high performance is developed. Single‐walled carbon nanotube/poly(3,4‐ethylenedioxythiophene) hybrid films with unique inner‐connected reticulation are adopted as electrodes for ultrathin structure and high electric conductivity. Then, based on two substrates with different surface energies, a stepwise lift‐off method is presented to peel off the ultrathin integrated supercapacitor from the substrates nondestructively. As a result of the high conductive hybrid electrodes and the thin electrolyte layer, the as‐designed supercapacitors (based on the total mass of two electrodes) achieve a good capacitance of 56 F g−1 and a superhigh power density of 332 kW kg−1, which manifest superior performance in contrast to the other devices fabricated by traditional electrodes. Meanwhile, the ultrashort response time of 11.5 ms enables the epidermal supercapacitor (SC‐E) work for high‐power units. More importantly, the free‐standing structure and outstanding flexibility (105 times bending) endow the SC‐E with excellent compatibility to be integrated and work in the next generation of smart and epidermal systems.An epidermal supercapacitor with micrometer‐thickness and high performance is developed by the combination of single‐walled carbon nanotube/poly(3,4‐ethylenedioxythiophene) hybrid electrodes and a stepwise lift‐off technique. The free‐standing supercapacitor has superior capacity and a superhigh power density of 332 kW kg−1 as well as outstanding flexibility. It is promising for integration into future smart and epidermal systems.
      PubDate: 2016-09-22T06:20:41.901036-05:
      DOI: 10.1002/adfm.201603480
  • Dual‐Targeting Heparin‐Based Nanoparticles that Re‐Assemble in Blood
           for Glioma Therapy through Both Anti‐Proliferation and
    • Authors: Jihui Wang; Yuantao Yang, Yonghong Zhang, Min Huang, Zhenjun Zhou, Wanxian Luo, Jiao Tang, Jianguo Wang, Qian Xiao, Huajian Chen, Yingqian Cai, Xinlin Sun, Ying Wang, Yiquan Ke
      Abstract: The efficient and specific delivery of nanoparticles (NPs) to brain tumors is crucial for successful glioma treatment. Heparin‐based polymers decorated with two peptides self‐assemble into multi‐functional NPs that specifically target glioma cells. These NPs re‐self‐assemble to a smaller size in blood, which is beneficial for in‐vivo brain drug delivery. The hydrodynamic size of one type of these NPs is 63 ± 11 nm under blood‐mimic conditions (10% fetal bovine serum), but it is 164 ± 16 nm in water. Additionally their zeta potential is more neutral in the blood‐mimic conditions. Transmission electron microscopy reveals the morphology of the spherical NPs. In vitro experiments demonstrate that the NPs exhibit a high cellular uptake and the ability to efficiently discourage proliferation, endothelial‐lined vessels, and vasculogenic mimicry. In vivo studies demonstrate that the NPs can by‐pass the normal blood–brain and blood–(brain tumor) barriers and specifically accumulate in glioma tissues; moreover, they present an excellent anti‐glioma effect in subcutaneous/intracranial glioma‐bearing mice. Their superiority is due to their appropriate size in blood and the synergic effect arising from their targeting of two different receptors. The data suggests that these NPs are ideal for anti‐glioma therapy.Nanoparticles (NPs) are formed when a heparin‐based polymer containing two different peptides self‐assembles in water. The peptides target different cell receptors, and their structures enable the NPs to rearrange and re‐self‐assemble in blood. Their dual‐targeting capability and resulting size in blood make them suitable for in vivo brain drug delivery. By‐passing the vascular–tumor barrier and accumulating specifically in glioma, these NPs exhibit an excellent anti‐glioma effect in mice.
      PubDate: 2016-09-22T06:20:37.080818-05:
      DOI: 10.1002/adfm.201602810
  • Temperature Sensors: Robust and Stable Ratiometric Temperature Sensor
           Based on Zn–In–S Quantum Dots with Intrinsic Dual‐Dopant Ion
           Emissions (Adv. Funct. Mater. 40/2016)
    • Authors: Sheng Cao; Jinju Zheng, Jialong Zhao, Zuobao Yang, Minghui Shang, Chengming Li, Weiyou Yang, Xiaosheng Fang
      Pages: 7197 - 7197
      Abstract: A robust and stable ratiometric temperature sensor based on Zn‐In‐S quantum dots (QDs) with intrinsic dual‐dopant ion emissions is reported by W.Y. Yang, X.S. Fang, and co‐workers on page 7224. The environment‐friendly co‐doped QD sensor exhibits an excellent stability with almost no hysteresis in cycles. The device is promising for challenging applications in future optical nanothermometry.
      PubDate: 2016-10-25T11:30:38.409509-05:
      DOI: 10.1002/adfm.201670260
  • Liquid Marbles: Stimuli‐Responsive Liquid Marbles: Controlling
           Structure, Shape, Stability, and Motion (Adv. Funct. Mater. 40/2016)
    • Authors: Syuji Fujii; Shin‐ichi Yusa, Yoshinobu Nakamura
      Pages: 7198 - 7198
      Abstract: Liquid marbles are liquid‐in‐gas dispersed systems stabilized by solid particles adsorbed at the gas‐liquid interface. The recent progress made in stimuli‐responsive liquid marbles, whose structure, stability and movement can be controlled by external stimuli such as pH, temperature, light, magnetic and electric fields, ultrasonic, mechanical stress and organic solvents, is reviewed by S. Fujii and co‐workers on page 7206.
      PubDate: 2016-10-25T11:30:39.91081-05:0
      DOI: 10.1002/adfm.201670261
  • Contents: (Adv. Funct. Mater. 40/2016)
    • Pages: 7199 - 7205
      PubDate: 2016-10-25T11:30:38.300261-05:
      DOI: 10.1002/adfm.201670262
  • Stimuli‐Responsive Liquid Marbles: Controlling Structure, Shape,
           Stability, and Motion
    • Authors: Syuji Fujii; Shin‐ichi Yusa, Yoshinobu Nakamura
      Pages: 7206 - 7223
      Abstract: “Liquid marbles” are liquid‐in‐gas dispersed systems stabilized by hydrophobic solid particles adsorbed at the gas‐liquid interface. The structure, stability and movement of these liquid marbles can be controlled by external stimuli such as pH, temperature, light, magnetic and electric fields, ultrasonic, mechanical stress and organic solvents. Stimuli‐responsive modes can be categorized into five classes: (i) liquid marbles whose stability can be controlled by adsorption/desorption of solid particles to/from liquid surfaces, (ii) liquid marbles that can open and close their particle‐coated surface by moving particles to and from the gas‐liquid surface, (iii) liquid marbles that can move, (iv) liquid marbles that can change their shape and (v) liquid marbles that can be split. As a result of these stimuli‐responsive characteristics, liquid marbles offer potential in the areas of controlled encapsulation, delivery and release.Liquid marbles are liquid‐in‐gas dispersed systems stabilized by solid particles adsorbed at the gas‐liquid interface. The recent progress made in stimuli‐responsive liquid marbles, whose structure, stability and movement can be controlled by external stimuli such as pH, temperature, light, magnetic and electric fields, ultrasonic, mechanical stress and organic solvents, is reviewed.
      PubDate: 2016-08-22T05:37:02.496488-05:
      DOI: 10.1002/adfm.201603223
  • Robust and Stable Ratiometric Temperature Sensor Based on Zn–In–S
           Quantum Dots with Intrinsic Dual‐Dopant Ion Emissions
    • Authors: Sheng Cao; Jinju Zheng, Jialong Zhao, Zuobao Yang, Minghui Shang, Chengming Li, Weiyou Yang, Xiaosheng Fang
      Pages: 7224 - 7233
      Abstract: Dual emission quantum dots (QDs) have attracted considerable interest as a novel phosphor for constructing ratiometric optical thermometry because of its self‐referencing capability. In this work, the exploration of codoped Zn–In–S QDs with dual emissions at ≈512 and ≈612 nm from intrinsic Cu and Mn dopants for ratiometric temperature sensing is reported. It is found that the dopant emissions can be tailored by adjusting the Mn‐to‐Cu concentration ratios, enabling the dual emissions in a tunable manner. The energy difference between the conduction band of the host and Cu dopant states is considered as the key for the occurrence of Mn ion emission. The as‐constructed QD ratiometric temperature sensor exhibits a totally robust stability with a fluctuation of ≈ICu/Itot versus times lower than 1% and almost no hysteresis in cycles over a broad window of 100–320 K. This discovery represents that the present cadmium‐free, intrinsic dual‐emitting codoped QDs can open a new door for the synthesis of novel QDs with stable dual emissions, which poise them well for challenging applications in optical nanothermometry.A robust and stable ratiometric temperature sensor based on Zn–In–S QDs with intrinsic dual‐dopant ion emissions is investigated. The fluctuation of ≈ICu/Itot versus time is lower than 1% and the sensor shows almost no hysteresis in cycles over a broad operating temperature window from 100 to 320 K.
      PubDate: 2016-09-13T07:02:54.525004-05:
      DOI: 10.1002/adfm.201603201
  • Highly Conductive and Environmentally Stable Organic Transparent
           Electrodes Laminated with Graphene
    • Authors: Jae Hwan Chu; Do Hee Lee, Junhyeon Jo, Sung Youb Kim, Jung‐Woo Yoo, Soon‐Yong Kwon
      Pages: 7234 - 7243
      Abstract: Improving the lifetime and the operational and thermal stability of organic thin‐film materials while maintaining high conductivity and mechanical flexibility is critical for flexible electronics applications. Here, it is reported that highly conductive and environmentally stable organic transparent electrodes (TEs) can be fabricated by mechanically laminating poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) films containing dimethylsulfoxide and Zonyl fluorosurfactant (PDZ films) with a monolayer graphene barrier. The proposed lamination process allows graphene to be coated onto the PDZ films uniformly and conformally with tight interfacial binding, free of wrinkles and air gaps. The laminated films exhibit an outstanding room‐temperature hole mobility of ≈85.1 cm2 V−1 s−1 since the graphene can serve as an effective bypass for charge carriers. The significantly improved stability of the graphene‐laminated TEs against high mechanical/thermal stress, humidity, and ultraviolet irradiation is particularly promising. Furthermore, the incorporation of the graphene barrier increases the expected lifetime of the TEs by more than two orders of magnitude.Highly conductive and environmentally stable organic transparent electrodes (TEs) are fabricated by mechanically laminating poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) films containing dimethylsulfoxide and Zonyl fluorosurfactant with a monolayer graphene barrier. The proposed lamination process allows graphene to be coated on organic surfaces uniformly and conformally and the graphene laminated TEs possess exceptional electrical and barrier properties with significantly improved operational and thermal stability.
      PubDate: 2016-09-04T22:20:18.497781-05:
      DOI: 10.1002/adfm.201602125
  • Multiresponsive Bidirectional Bending Actuators Fabricated by a
           Pencil‐on‐Paper Method
    • Authors: Mingcen Weng; Peidi Zhou, Luzhuo Chen, Lingling Zhang, Wei Zhang, Zhigao Huang, Changhong Liu, Shoushan Fan
      Pages: 7244 - 7253
      Abstract: Recently, actuating materials based on carbon nanotubes or graphene have been widely studied. However, present carbon‐based actuating materials are mostly driven by a single stimulus (humidity, light, electricity, etc.), respectively, which means that the application conditions are limited. Here, a new kind of multiresponsive actuating material which can be driven by humidity, light, and electricity is proposed, so it can be used in various conditions. The fabrication is based on the simplest pencil‐on‐paper method, in which the pencil and paper are both low‐cost and easily obtained daily materials. The actuation effect is more remarkable due to a dual‐mode actuation mechanism, which leads to an ultralarge actuation (bending curvature up to 2.6 cm−1). Elaborately designed, the actuator can further exhibit a bidirectional bending actuation, which is a significant improvement compared with previous reported thermal actuators. What is more, a colorful biomimetic flower and a smart curtain are also fabricated, fully utilizing the printable characteristic of the paper and multiresponsive characteristic of the actuator. It is assumed that the newly designed actuating material has great potential in the fields of lab‐on‐paper devices, artificial muscles, robotics, biomimics, and smart household materials.A multiresponsive actuator based on graphite, paper, and polymer composite shows large bidirectional bending actuations when it is driven by humidity, light, and electricity. The fabrication is based on the simplest pencil‐on‐paper method. A colorful biomimetic flower and a smart curtain are also fabricated, fully utilizing the printable characteristic of the paper and multiresponsive characteristic of the actuator.
      PubDate: 2016-09-13T07:02:50.066731-05:
      DOI: 10.1002/adfm.201602772
  • Inducing Elasticity through Oligo‐Siloxane Crosslinks for Intrinsically
           Stretchable Semiconducting Polymers
    • Authors: Ging‐Ji Nathan Wang; Leo Shaw, Jie Xu, Tadanori Kurosawa, Bob C. Schroeder, Jin Young Oh, Stephanie J. Benight, Zhenan Bao
      Pages: 7254 - 7262
      Abstract: The promise of wearable and implantable devices has made stretchable organic semiconductors highly desirable. Though there are increasing attempts to design intrinsically stretchable conjugated polymers, their performance in terms of charge carrier mobility and maximum fracture strain is still lacking behind extrinsic approaches (i.e., buckling, Kirigami interconnects). Here, polymer crosslinking with flexible oligomers is applied as a strategy to reduce the tensile modulus and improve fracture strain, as well as fatigue resistance for a high mobility diketopyrrolopyrrole polymer. These polymers are crosslinked with siloxane oligomers to give stretchable films stable up to a strain ε = 150% and 500 strain‐and‐release cycles of 100% strain without the formation of nanocracks. Organic field‐effect transistors are prepared to assess the electrical properties of the crosslinked film under cyclic strain loading. An initial average mobility (μavg) of 0.66 cm2 V−1 s−1 is measured at 0% strain. A steady μavg above 0.40 cm2 V−1 s−1 is obtained in the direction perpendicular to the strain direction after 500 strain‐and‐release cycles of 20% strain. The μavg in the direction parallel to strain, however, is compromised due to the formation of wrinkles.Improved elastic property in diketopyrrolopyrrole polymer is achieved by crosslinking with a flexible siloxane oligomer. An enhancement in fracture strain and yielding point and a decrease in tensile modulus with film crystalinity are observed. The improved fatigue resistance is attributed to the covalent crosslinks that prevent irreversible sliding between polymer chains during cyclic loading.
      PubDate: 2016-08-29T10:30:29.918246-05:
      DOI: 10.1002/adfm.201602603
  • Microwave Combustion for Modification of Transition Metal Oxides
    • Authors: Jun Wan; Xu Yao, Xiang Gao, Xu Xiao, Tianqi Li, Jiabin Wu, Wanmei Sun, Zhimi Hu, Huimin Yu, Liang Huang, Meilin Liu, Jun Zhou
      Pages: 7263 - 7270
      Abstract: The introduction of oxygen vacancy for transition metal oxide is an effective method to tune their conductivity. Here, microwave combustion method is used to quickly synthesize reduced metal oxides and graphene hybrid composite in several minutes. Among these as‐synthesized composites, the reduced orthorhombic Nb2O5 and graphene oxide (rNb2O5/rGO) composite demonstrates great electrochemical performance with a reversible specific capacity of 726.2 C g−1 at 2 mV s−1 in organic electrolyte as well as a good capacity retention of 87% after 3000 cycles at 10 A g−1. It is believed that this strategy can be a common route to quickly produce oxygen vacancy in oxides and satisfy much more application requirements even for the possibility of industrialization.A fast and facile method is reported to introduce oxygen vacancies for various metal oxides through microwave combustion induced carbon reduction method. This provides a common route to quickly produce oxygen vacancies in oxides and satisfies the requirements for a variety of applications.
      PubDate: 2016-09-04T22:15:26.350752-05:
      DOI: 10.1002/adfm.201603125
  • Unleashing Strain Induced Ferroelectricity in Complex Oxide Thin Films via
           Precise Stoichiometry Control
    • Authors: Ryan C. Haislmaier; Everett D. Grimley, Michael D. Biegalski, James M. LeBeau, Susan Trolier‐McKinstry, Venkatraman Gopalan, Roman Engel‐Herbert
      Pages: 7271 - 7279
      Abstract: Strain tuning has emerged as a powerful means to enhance properties and to induce otherwise unattainable phenomena in complex oxide films. However, by employing strain alone, the predicted properties sometimes fail to emerge. In this work, the critical role of precise stoichiometry control for realizing strain‐induced ferroelectricity in CaTiO3 films is demonstrated. An adsorption controlled growth window is discovered for CaTiO3 films grown by hybrid molecular beam epitaxy, which ensures an excellent control over the Ti:Ca atomic percent ratio of
      PubDate: 2016-09-05T01:40:40.462095-05:
      DOI: 10.1002/adfm.201602767
  • Electrodes: Ferromagnetic, Folded Electrode Composite as a Soft Interface
           to the Skin for Long‐Term Electrophysiological Recording (Adv. Funct.
           Mater. 40/2016)
    • Authors: Kyung‐In Jang; Han Na Jung, Jung Woo Lee, Sheng Xu, Yu Hao Liu, Yinji Ma, Jae‐Woong Jeong, Young Min Song, Jeonghyun Kim, Bong Hoon Kim, Anthony Banks, Jean Won Kwak, Yiyuan Yang, Dawei Shi, Zijun Wei, Xue Feng, Ungyu Paik, Yonggang Huang, Roozbeh Ghaffari, John A. Rogers
      Pages: 7280 - 7280
      Abstract: On page 7281, J. A. Rogers and co‐workers describe a ferromagnetic, folded electrode composite. The image demonstrates the ability of the material to hold a coin magnet through a glass slide with strong magnetic attractive force. The material forms irritation‐free but robust contacts to the skin and forms dimensionally stable geometries, making it promising for long‐term electrophysiological monitoring.
      PubDate: 2016-10-25T11:30:39.953053-05:
      DOI: 10.1002/adfm.201670264
  • Ferromagnetic, Folded Electrode Composite as a Soft Interface to the Skin
           for Long‐Term Electrophysiological Recording
    • Authors: Kyung‐In Jang; Han Na Jung, Jung Woo Lee, Sheng Xu, Yu Hao Liu, Yinji Ma, Jae‐Woong Jeong, Young Min Song, Jeonghyun Kim, Bong Hoon Kim, Anthony Banks, Jean Won Kwak, Yiyuan Yang, Dawei Shi, Zijun Wei, Xue Feng, Ungyu Paik, Yonggang Huang, Roozbeh Ghaffari, John A. Rogers
      Pages: 7281 - 7290
      Abstract: A class of ferromagnetic, folded, soft composite material for skin‐interfaced electrodes with releasable interfaces to stretchable, wireless electronic measurement systems is introduced. These electrodes establish intimate, adhesive contacts to the skin, in dimensionally stable formats compatible with multiple days of continuous operation, with several key advantages over conventional hydrogel‐based alternatives. The reported studies focus on aspects ranging from ferromagnetic and mechanical behavior of the materials systems, to electrical properties associated with their skin interface, to system‐level integration for advanced electrophysiological monitoring applications. The work combines experimental measurement and theoretical modeling to establish the key design considerations. These concepts have potential uses across a diverse set of skin‐integrated electronic technologies.A ferromagnetic, folded, soft‐electrode composite material with long‐term usage and system‐level integration in electrophysiological monitoring is introduced. Systematic investigations including the ferromagnetism behaviors, mechanical properties, electrical interfaces to the skin, and their materials aspects are carried out. The electrodes provide advantages in non‐irritating contacts to the skin, dimensionally stable geometries, and robust bonding to the skin and the measurement platforms.
      PubDate: 2016-09-09T01:50:04.795777-05:
      DOI: 10.1002/adfm.201603146
  • New Drug‐Structure‐Directing Agent Concept: Inherent Pharmacological
           Activity Combined with Templating Solid and Hollow‐Shell Mesostructured
           Silica Nanoparticles
    • Authors: Victoria Morales; María Gutiérrez‐Salmerón, Moisés Balabasquer, Josefa Ortiz‐Bustos, Ana Chocarro‐Calvo, Custodia García‐Jiménez, Rafael A. García‐Muñoz
      Pages: 7291 - 7303
      Abstract: One of the major challenges in medicine is the delivery and control of drug release over time. Current approaches take advantage of mesostructured silica nanoparticles (MSNs) as carriers but suffer several problems including complex synthesis that requires sequential steps for (1) removal of surfactants and (2) functionalization of MSNs to allow upload of the drugs. Here, a novel solution is presented to these restrictions: the design of drug‐structure‐directing agents (DSDAs) with dual inherent pharmacological activity and ability to direct the formation of solid and hollow‐shell MSNs. Pharmacologically active DSDAs obtained by amidation of drugs with fatty acids are allowed to form micelles, around which the inorganic species self‐assembled to form MSNs. Since the DSDAs direct the formation of MSNs, the steps to remove surfactants, functionalization, and drug upload are not required. The MSNs thus prepared provide sustained release of the drug over more than six months, as well as rapid cellular internalization by both physiological and tumoral human colon cells without affecting cell viability. Moreover, the gradual intracellular release of both, the active drug and lipid moiety with potential nutraceutical properties is proved. MSN particles designed with this approach are promising vehicles for controlled and sustained intra‐or extracellular drug‐delivery.The design of new drug‐structure‐directing agents with inherent pharmacological and nutraceutical activity and ability to direct the formation of mesostructured silica nanoparticles (MSNs) is presented. Sustained release of the drug from MSNs is observed during months. MSNs are internalized by both normal and tumoral human colon cells and cell viability is largely unaffected by MSNs. Internalization of MSNs and intracellular release of their content are shown.
      PubDate: 2016-08-31T01:46:07.402131-05:
      DOI: 10.1002/adfm.201505073
  • Supported Lipid Bilayer Assembly on PEDOT:PSS Films and Transistors
    • Authors: Yi Zhang; Sahika Inal, Chih‐Yun Hsia, Magali Ferro, Marc Ferro, Susan Daniel, Roisin M. Owens
      Pages: 7304 - 7313
      Abstract: Lipid bilayers are widely employed as a model system to investigate interactions between cells and their environment. Supported lipid bilayers (SLB) with integrated transmembrane proteins are emerging as a preferred platform for sensing applications. Challenges lie in the generation of SLB on surfaces which allow transduction of signals for characterization of lipid bilayer and incorporated transmembrane proteins. For the first time, the formation of SLBs is shown on films of the conducting polymer, poly(3,4‐ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS), using traditional methods for characterizing lipid bilayer quality and function (QCM‐D, FRAP) combined with impedance spectroscopy. Further, partial formation of SLBs on PEDOT:PSS based organic electrochemical transistors (OECTs) is successfully demonstrated, as well as the ability to integrate and sense the ion pore α‐hemolysin, confirming the sensitivity of the OECT as a transducer of biological membrane function. This work represents a highly promising first step toward the use of such OECTs for functional readout of transmembrane proteins in their native environment.Supported lipid bilayers represent an excellent substitute for live cells, to study membrane protein function. For the first time, the integration of biologically functioning supported lipid bilayers is shown, with conducting polymer films and transistors. Traditional methods for characterizing lipid bilayer quality and function are compared with electrical readouts using both impedance spectroscopy and the organic electrochemical transistor. This represents a first, important step toward readout of such systems with organic transistors.
      PubDate: 2016-09-06T01:21:49.189239-05:
      DOI: 10.1002/adfm.201602123
  • Effective Codelivery of lncRNA and pDNA by Pullulan‐Based Nanovectors
           for Promising Therapy of Hepatocellular Carcinoma
    • Authors: Yanli Ren; Rui‐Quan Li, Yi‐Ran Cai, Tian Xia, Ming Yang, Fu‐Jian Xu
      Pages: 7314 - 7325
      Abstract: Hepatocellular carcinoma (HCC) is one of the most common cancers. Maternally expressed gene 3 (MEG3, one kind of long noncoding RNA [lncRNA]) can act as a tumor suppressor and regulate P53 target gene expression. However, lncRNA MEG3 demonstrates relatively low or no expression in human HCC. This study provides a promising concept to codeliver lncRNA and pDNA for cancer therapy. As proof‐of‐concept, the pcDNA‐MEG3 and pcDNA‐P53 plasmids‐condensed nanocomplexes with the liver‐targeting polycation gene vector, pullulan‐based ethanolamine‐modified poly(glycidyl methacrylate) (denoted as PuPGEA), are proposed to codeliver lncRNA and pDNA to treat HCC. Pullulan‐containing nanovectors are shown to be able to effectively mediate gene delivery in liver cells. To assess gene delivery performances of PuPGEA, a series of assays such as in vitro gene transfection, HCC cell proliferation, colony formation, migration, matrigel transwell assays, and in vivo xenograft animal models are carried out. The codelivery system with PuPGEA/(MEG3+P53) nanocomplexes demonstrates additive effects in suppressing HCC compared to PuPGEA/MEG3 or PuPGEA/P53 nanocomplexes alone. These results suggest that codelivery of lncRNA and pDNA by polycation nanovectors is a promising method to treat cancers.Codelivery of MEG3 and P53 gene by nanocomplexes containing liver‐targeting pullulan‐based ethanolamine‐modified poly(glycidyl methacrylate) (PuPGEA) is proposed to suppress hepatocellular carcinoma.
      PubDate: 2016-09-08T07:50:47.739596-05:
      DOI: 10.1002/adfm.201603041
  • Criticality: Concept to Enhance the Piezoelectric and Electrocaloric
           Properties of Ferroelectrics
    • Authors: Florian Weyland; Matias Acosta, Jurij Koruza, Patrick Breckner, Jürgen Rödel, Nikola Novak
      Pages: 7326 - 7333
      Abstract: Compositional engineering with a focus on structural phase transitions has been considered as the most important approach for enhancement of the functional properties of ferroelectric materials due to the critical fluctuation of physical properties. Of special interest are electric‐field‐induced phase transitions, which can terminate in a liquid–vapor‐type critical point with a strong enhancement of functional properties. Whereas the critical point in liquid–vapor space considers changes in temperature and pressure, the critical point in this study is placed in electric field–temperature diagrams. In single crystals, temperature and electric field of a critical point are sharply defined and therefore not appealing for practical applications. However, in ceramics, it is demonstrated that the orientational dependence of the critical point leads to a broadened temperature and electric field range. The presence of a diffuse critical point in ceramics provides a conceptually novel approach for the enhancement of functional properties, such as piezoelectric and electrocaloric (EC) responses, as validated here on the example of the 0.75Bi1/2Na1/2TiO3‐0.25SrTiO3 lead‐free relaxor ferroelectric ceramics. The realization of a broad criticality range will further facilitate the development of the piezoelectric and EC materials and provide an alternative concept to manipulate the functional properties by application of an electric field.The concept of criticality provides an alternative approach to manipulate the functional properties of ferroelectrics by an electric field. The inherent randomness of the grain orientations in polycrystalline samples leads to the existence of a diffuse critical point, resulting in enhanced piezoelectric and electrocaloric properties over a broad temperature and electric field range.
      PubDate: 2016-09-05T01:40:29.936982-05:
      DOI: 10.1002/adfm.201602368
  • Hollow Manganese Silicate Nanotubes with Tunable Secondary Nanostructures
           as Excellent Fenton‐Type Catalysts for Dye Decomposition at Ambient
    • Authors: Shu‐Meng Hao; Jin Qu, Zhong‐Shuai Zhu, Xiao‐Ying Zhang, Qian‐Qian Wang, Zhong‐Zhen Yu
      Pages: 7334 - 7342
      Abstract: Fast diffusion rate of ions and sufficiently exposed active sites are important for catalysts. As a superior but rarely studied Fenton‐type catalyst, unsatisfactory ion diffusion rate of manganese silicate is the exact obstacle for improving its catalytic activity. Here, hierarchical manganese silicate hollow nanotubes (MnSNTs) assembled by tunable secondary structures are precisely fabricated by an efficient hydrothermal method and systematically investigated as Fenton‐type catalysts for the first time. The open end and thin mesoporous walls of the hollow nanotubes help shorten the diffusion pathway of ions and enhance the mass transport. Moreover, the numerous standing small nanosheets endow MnSNTs with higher specific surface area and larger pore volume than the large nanosheets and nanoparticles, and thus expose more active sites for adsorption and catalytic decomposition. MnSNTs are highly efficient in adsorption and catalytic decomposition of cationic dyes with an excellent recycling stability. About 98.1% of methylene blue is catalytically decomposed in 45 min at an ambient temperature of 25 °C. When the temperature increases to 60 °C, only 2 min are required, with a 530% higher kinetic constant than reported.Hierarchical manganese silicate hollow nanotubes assembled by tunable secondary structures are fabricated and systematically investigated as Fenton‐type catalysts. About 98.1% of methylene blue is decomposed in 45 min at 25 °C. When the temperature increases to 60 °C, only 2 min are required, with a 530% higher kinetic constant than reported.
      PubDate: 2016-09-07T02:25:32.949394-05:
      DOI: 10.1002/adfm.201603315
  • Synthesis of Optically Complex, Porous, and Anisometric Polymeric
           Microparticles by Templating from Liquid Crystalline Droplets
    • Authors: Xiaoguang Wang; Emre Bukusoglu, Daniel S. Miller, Marco A. Bedolla Pantoja, Jie Xiang, Oleg D. Lavrentovich, Nicholas L. Abbott
      Pages: 7343 - 7351
      Abstract: It is demonstrated that aqueous dispersions of micrometer‐sized liquid crystal (LC) droplets provide the basis of a general and facile methodology for the templated synthesis of spherical and nonspherical polymeric microparticles with complex internal structure and porosity. Specifically, nematic droplets of reactive (RM257)/nonreactive mesogens with distinct internal configurations are prepared using a range of approaches, the reactive mesogens are photopolymerized, and then the nonreactive mesogens are extracted to yield polymeric particles. It is found that LC droplets exhibiting bipolar, radial, axial or preradial configurations template the formation of spindle‐shaped, spherical, spherocylindrical or tear‐shaped polymeric microparticles, respectively. Each type of microparticle exhibits distinct optical signatures indicating the presence of an internal LC‐templated, anisotropic polymer network. In addition, by using a microfluidic system to generate monodisperse LC droplets containing 10%–40% wt/wt of RM257, spindle‐shaped microparticles with tailored aspect ratios ranging from 2.4 to 1.2 are formed. The mass density of spherical microparticles templated from radial LC droplets can be tuned to range from 0.2 to 0.6 g cm−3, revealing the introduction of porosity (confirmed by electron microscopy) with a volume‐average pore diameter of 39 ± 16 nm (obtained from nitrogen sorption isotherms).Liquid crystal droplets can be used as templates for the synthesis of optically complex, porous, and anisometric polymeric microparticles. The method, which involves emulsification of mixtures of reactive and nonreactive mesogens, photopolymerization, and extraction of the nonreactive mesogens, leads to the formation of spindle‐shaped, spherical, spherocylindrical or tear‐shaped particles while providing a control over both the porosity and internal configuration of the microparticles.
      PubDate: 2016-09-05T01:40:42.797728-05:
      DOI: 10.1002/adfm.201602262
  • Scissor‐Like Chiral Metamolecules for Probing Intracellular
           Telomerase Activity
    • Authors: Maozhong Sun; Liguang Xu, Pan Fu, Xiaoling Wu, Hua Kuang, Liqiang Liu, Chuanlai Xu
      Pages: 7352 - 7358
      Abstract: A DNA‐driven gold (Au) heterodimer for intracellular telomerase detection is fabricated. The highly biocompatible and intracellularly stable probe shows an active chiroptical property in the visible region, due to the scissor‐like configuration formed by prolate nanoparticles. Importantly, the telomerase activity is specifically quantified using circular dichroism intensity in situ after internalization of the heterodimer into cancer cells. Moreover, the results clearly illustrate that this method has a remarkable linear range from 0.8 × 10−12 to 32 × 10−12 IU, and the limit of detection for telomerase activity is 1.7 × 10−15 IU in a single HeLa cell. This strategy paves the way for chirality‐based ultrasensitive detection of intracellular cancer markers.In this work, DNA‐driven scissor‐like chiral metamolecules for intracellular telomerase detection are fabricated. The telomerase activity is specifically quantified using circular dichroism intensity in situ. The results show that this method has a remarkable linear range from 0.8 × 10−12 to 32 × 10−12 IU, and the limit of detection for telomerase activity is 1.7 × 10−15 IU in a single HeLa cell.
      PubDate: 2016-08-16T08:55:38.139598-05:
      DOI: 10.1002/adfm.201601942
  • Tunable Band‐Selective UV‐Photodetectors by 3D Self‐Assembly of
           Heterogeneous Nanoparticle Networks
    • Authors: Noushin Nasiri; Renheng Bo, Tak Fu Hung, Vellaisamy A. L. Roy, Lan Fu, Antonio Tricoli
      Pages: 7359 - 7366
      Abstract: Accurate detection of ultraviolet radiation is critical to many technologies including wearable devices for skin cancer prevention, optical communication systems, and missile launch detection. Here, a nanoscale architecture is presented for band‐selective UV‐photodetectors, which features unique tunability and miniaturization potential. The device layout relies on the 3D integration of ultraporous layers of tailored nanoparticles. By tailoring the transmittance window between the indirect band gap of TiO2 nanoparticles and the sharp edge of the direct band gap of ZnO, a band‐selective photoresponse is achieved with tunable bandwidth to less than 30 nm and photo‐ to dark‐current ratios of several millions at a light intensity of 86 μW cm−2 and operation bias of 1 V. The potential of this integrated morphology is shown by fabrication of the first inherent UVA photodetector with selectivity against the edge of the UVB and visible light of nearly 60 times. This tunable architecture and nanofabrication approach are compatible with state‐of‐the micromachining technologies and provide a flexible solution for the engineering of wearable band‐selective photodetectors.A 3D solid‐state architecture for tunable band‐selective ultraviolet‐photodetectors with superior optoelectronic properties is presented. The device layout relies on the integration of ultraporous metal‐oxide nanoparticle networks. Tailoring the transmittance window between an indirect bandgap semiconductor and the sharp edge of a direct band structure results in outstanding ultraviolet‐photoresponse at low light density with tunable bandwidth to less than 30 nm.
      PubDate: 2016-09-05T01:35:35.033025-05:
      DOI: 10.1002/adfm.201602195
  • Flexible Transparent Electrodes: Highly Conductive and Environmentally
           Stable Organic Transparent Electrodes Laminated with Graphene (Adv. Funct.
           Mater. 40/2016)
    • Authors: Jae Hwan Chu; Do Hee Lee, Junhyeon Jo, Sung Youb Kim, Jung‐Woo Yoo, Soon‐Yong Kwon
      Pages: 7367 - 7367
      Abstract: J.‐W. Yoo, S.‐Y. Kwon, and co‐workers introduce a highly conductive and environmentally stable organic transparent electrode (TE), laminated with graphene barrier, on page 7234. Structural, electrical, and barrier properties as well as operational and thermal stability of TEs are systematically investigated. The electrodes possess excellent operational and thermal stability by employing 2D carbon materials while maintaining high conductivity and mechanical flexibility.
      PubDate: 2016-10-25T11:30:42.302425-05:
      DOI: 10.1002/adfm.201670265
  • Actuators: Multiresponsive Bidirectional Bending Actuators Fabricated by a
           Pencil‐on‐Paper Method (Adv. Funct. Mater. 40/2016)
    • Authors: Mingcen Weng; Peidi Zhou, Luzhuo Chen, Lingling Zhang, Wei Zhang, Zhigao Huang, Changhong Liu, Shoushan Fan
      Pages: 7368 - 7368
      Abstract: A multi‐responsive actuator based on paper and polymer composite is fabricated by a Pencil‐on‐Paper method, which is described by L. Chen, W. Zhang, C. Liu, and co‐workers on page 7244. A colorful biomimetic flower and a smart curtain are also fabricated to demonstrate the applications. This work has great potential in the fields of lab‐on‐paper devices, artificial muscles, robotics, and biomimics.
      PubDate: 2016-10-25T11:30:38.247906-05:
      DOI: 10.1002/adfm.201670266
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