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  Subjects -> CHEMISTRY (Total: 881 journals)
    - ANALYTICAL CHEMISTRY (54 journals)
    - CHEMISTRY (616 journals)
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CHEMISTRY (616 journals)                  1 2 3 4 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 14)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Hybrid Journal   (Followers: 43)
ACS Chemical Neuroscience     Hybrid Journal   (Followers: 21)
ACS Combinatorial Science     Hybrid Journal   (Followers: 23)
ACS Macro Letters     Hybrid Journal   (Followers: 25)
ACS Medicinal Chemistry Letters     Hybrid Journal   (Followers: 41)
ACS Nano     Hybrid Journal   (Followers: 281)
ACS Photonics     Hybrid Journal   (Followers: 14)
ACS Symposium Series     Full-text available via subscription  
ACS Synthetic Biology     Hybrid Journal   (Followers: 24)
Acta Chemica Iasi     Open Access   (Followers: 5)
Acta Chimica Slovaca     Open Access   (Followers: 2)
Acta Chimica Slovenica     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 7)
Acta Scientifica Naturalis     Open Access   (Followers: 3)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 7)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 9)
Adsorption Science & Technology     Open Access   (Followers: 6)
Advanced Functional Materials     Hybrid Journal   (Followers: 57)
Advanced Science Focus     Free   (Followers: 5)
Advances in Chemical Engineering and Science     Open Access   (Followers: 67)
Advances in Chemical Science     Open Access   (Followers: 18)
Advances in Chemistry     Open Access   (Followers: 21)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 19)
Advances in Drug Research     Full-text available via subscription   (Followers: 24)
Advances in Environmental Chemistry     Open Access   (Followers: 5)
Advances in Enzyme Research     Open Access   (Followers: 10)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 25)
Advances in Nanoparticles     Open Access   (Followers: 15)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 16)
Advances in Polymer Science     Hybrid Journal   (Followers: 44)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Science and Technology     Full-text available via subscription   (Followers: 12)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 3)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Al-Kimia : Jurnal Penelitian Sains Kimia     Open Access  
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 65)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 20)
American Journal of Chemistry     Open Access   (Followers: 30)
American Journal of Plant Physiology     Open Access   (Followers: 11)
American Mineralogist     Hybrid Journal   (Followers: 15)
Analyst     Full-text available via subscription   (Followers: 38)
Angewandte Chemie     Hybrid Journal   (Followers: 167)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 243)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 5)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 4)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 9)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 12)
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     Open Access   (Followers: 2)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 9)
Applied Spectroscopy     Full-text available via subscription   (Followers: 23)
Applied Surface Science     Hybrid Journal   (Followers: 32)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 1)
Asian Journal of Biochemistry     Open Access   (Followers: 2)
Atomization and Sprays     Full-text available via subscription   (Followers: 4)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access  
Biochemical Pharmacology     Hybrid Journal   (Followers: 10)
Biochemistry     Hybrid Journal   (Followers: 356)
Biochemistry Insights     Open Access   (Followers: 6)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 10)
Bioinspired Materials     Open Access   (Followers: 5)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 2)
Biomacromolecules     Hybrid Journal   (Followers: 21)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 7)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 5)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 131)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 86)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 2)
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: 1)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 3)
Cakra Kimia (Indonesian E-Journal of Applied Chemistry)     Open Access  
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Hybrid Journal   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 6)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 70)
Catalysis for Sustainable Energy     Open Access   (Followers: 8)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 7)
Catalysis Science and Technology     Free   (Followers: 8)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 10)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 20)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 74)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 26)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Hybrid Journal   (Followers: 22)
Chemical Reviews     Hybrid Journal   (Followers: 190)
Chemical Science     Open Access   (Followers: 25)
Chemical Technology     Open Access   (Followers: 26)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 56)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 24)
ChemInform     Hybrid Journal   (Followers: 8)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 7)
Chemistry & Biology     Full-text available via subscription   (Followers: 32)
Chemistry & Industry     Hybrid Journal   (Followers: 7)
Chemistry - A European Journal     Hybrid Journal   (Followers: 159)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 16)
Chemistry and Materials Research     Open Access   (Followers: 21)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry International     Open Access   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 43)
Chemistry of Materials     Hybrid Journal   (Followers: 257)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry World     Full-text available via subscription   (Followers: 19)
Chemistry-Didactics-Ecology-Metrology     Open Access   (Followers: 1)
ChemistryOpen     Open Access   (Followers: 1)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 4)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 14)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 12)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 11)
Chromatographia     Hybrid Journal   (Followers: 24)
Chromatography     Open Access   (Followers: 2)
Chromatography Research International     Open Access   (Followers: 6)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Cogent Chemistry     Open Access   (Followers: 1)
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 11)
Colloids and Interfaces     Open Access  
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 6)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 4)
Combustion Science and Technology     Hybrid Journal   (Followers: 22)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Communications Chemistry     Open Access  
Composite Interfaces     Hybrid Journal   (Followers: 7)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 1)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 10)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 4)
Copernican Letters     Open Access   (Followers: 1)
Corrosion Series     Full-text available via subscription   (Followers: 6)
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 6)
Croatica Chemica Acta     Open Access  
Crystal Structure Theory and Applications     Open Access   (Followers: 4)
CrystEngComm     Full-text available via subscription   (Followers: 13)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Chromatography     Hybrid Journal  
Current Green Chemistry     Hybrid Journal  
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Microwave Chemistry     Hybrid Journal  
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Opinion in Molecular Therapeutics     Full-text available via subscription   (Followers: 14)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 69)
Current Trends in Biotechnology and Chemical Research     Open Access   (Followers: 3)
Dalton Transactions     Full-text available via subscription   (Followers: 23)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 12)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  

        1 2 3 4 | Last

Journal Cover
Carbon
Journal Prestige (SJR): 2.226
Citation Impact (citeScore): 7
Number of Followers: 70  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0008-6223
Published by Elsevier Homepage  [3159 journals]
  • Influence of interfaces on the transport properties of graphite revealed
           by nanometer thickness reduction
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Mahsa Zoraghi, José Barzola-Quiquia, Markus Stiller, Pablo D. Esquinazi, Irina Estrela-LopisWe investigated the influence of thickness reduction on the transport properties of graphite microflakes. Using oxygen plasma etching we decreased the thickness of highly oriented pyrolytic graphite (HOPG) microflakes from ∼100 nm to ∼20 nm systematically. Keeping current and voltage electrodes intact, the electrical resistance R(T), the magnetoresistance (MR) and Raman spectra were measured in every individual sample and after each etching step of a few nm. The results show that R(T) and MR can increase or decrease with the sample thickness in a non-systematic way. The results indicate that HOPG samples are inhomogeneous materials, in agreement with scanning transmission electron microscopy images and X-ray diffraction data. Our results further indicate that the quantum oscillations in the MR are not an intrinsic property of the ideal graphite structure but their origin is related to internal conducting interfaces.Graphical abstractThe sketch around the transmission electron picture taken from a HOPG sample of the presented studies, shows the position of the electrodes at the top graphene layer. These electrodes, protected by a SiN layer, remain after a gentle oxygen plasma etching we use to reduce the thickness of the sample between the electrodes. With this technique we were able to measure the changes in the transport properties after nanometer thinning of the sample. The results clearly show that the transport properties are highly a_ected by the internal interfaces at the surface region where the electrodes are fixed. The usual width and length of the measured microakes were a few micrometers with a thickness
       
  • A reduced graphene oxide/nitrogen, phosphorus doped porous carbon hybrid
           framework as sulfur host for high performance lithium-sulfur batteries
    • Abstract: Publication date: Available online 14 August 2018Source: CarbonAuthor(s): Juan Ren, Li Xia, Yibei Zhou, Qiaoji Zheng, Jie Liao, Dunmin LinLithium-sulfur (Li-S) batteries have attracted ever-increasing attentions because of intrinsically high theoretical energy density. However, the insulating property of sulfur and severe polysulfides shuttle effect tremendously hinder their practical applications. Herein, a N, P dual-doped 3D hierarchical porous hybrid carbon is successfully prepared for advanced Li-S batteries based on the combination of reduced graphene oxide (rGO) and goat hair derived biomass carbon (rGO/GPC) by a simple one-pot pyrolysis process. A proper amount of rGO (3%) decorated biomass carbon (rGO/GPC-2) possesses a N, P dual-doped 3D robust porous framework and good electrical conductivity, which can effectively improve the sulfur utilization and immobilize the polysulfides through both physical restriction and chemical adsorption. The as-fabricated rGO/GPC-2-S composite used as Li-S batteries cathode delivers a high initial capacity of 1420 mAh g-1 at 0.1 C and maintains a reversible capacity of 503mAh g-1 after 500 cycles at 1.0 C with an ultralow capacity decay of 0.070% per cycle and excellent rate performance with 500 mAh g-1 at 2.0 C. The enhanced electrochemical performance is attributed to the positive synergistic effect of N, P-dual doped polar porous structure and nonpolar highly conductive hybrid carbon matrix.Graphical abstractA N, P dual-doped 3D hierarchical porous hybrid carbon is prepared for high performance Li-S batteries based on the combination of reduced graphene oxide (rGO) and goat hair derived biomass carbon (rGO/GPC) by a simple one-pot pyrolysis process.Image
       
  • Hierarchical phosphorus hybrids with carbon nanotube veins and black
           phosphorus skins: Structure and lithium storage properties
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Dan Zhao, Lihui Zhang, Chengcheng Fu, Jialiang Huang, Hongyang Huang, Zhihui Li, Jinying Zhang, Chunming Niu Phosphorus structures are promising anode materials for lithium and sodium ion batteries. However, the cycle stability is a big challenge for most phosphorus anode materials due to pulverization. Black phosphorus has been demonstrated to have extremely high stability as anodes due to its layered features. Black phosphorus have been in situ grown to wrap hierarchical phosphorus hybrids with multi-walled carbon nanotubes (MWCNTs) veins. The electrochemical performances of the hierarchical phosphorus hybrids have been significantly enhanced due to the black phosphorus skins and wrapped amorphous and fibrous phosphorus. Extremely high cycle stability and high specific capacitiyes have been achieved by the new hierarchical phosphorus hybrids. A specific capacity of 560 mAh g−1 has been still obtained at a current rate of 500 mA g−1 after 250 cycles.Graphical abstractImage 1
       
  • Thermal annealing of graphite oxide under high pressure: An experimental
           and computational study
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Andreia Fernandes da Silva, Augusto Mohr Christmann, Tânia Maria Haas Costa, André Rodrigues Muniz, Naira Maria Balzaretti In this work, we investigate the effect of high pressures on thermal reduction of graphite oxide (GO) using a combination of different characterization techniques and atomistic computational simulations. GO samples were submitted simultaneously to different pressures (up to 7.7 GPa) and temperatures (up to 1500 °C) using a high-pressure chamber. Reactive molecular dynamics simulations were carried out to provide some insight on the observed structural transformations. The samples annealed at ambient pressure consisted of large sheets of reduced GO, containing defects. In contrast, the morphology of the samples processed at higher pressures and temperatures was similar to those of graphite nanocrystals (significantly smaller than the pristine GO sheets). The simulations results corroborated these observations, and helped to explain the reasons for the differences in the morphology of the material when submitted to different conditions. They showed that higher pressures induced a significant reduction on the interplanar volume, inhibiting the formation of gas molecules and enhancing the diffusion and redistribution of functional groups on the GO surfaces. A sequence of reaction and diffusion pathways led the functional groups to concentrate in some regions, causing the local tearing of the structure and formation of crystalline nanodomains as observed in the experiments.Graphical abstractImage 1
       
  • H2O2/UV layer-by-layer oxidation of multiwall carbon nanotubes: The
           “onion effect” and the control of the degree of surface crystallinity
           and diameter
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Viviana Jehová González, Sofía Magdalena Vega-Díaz, Aarón Morelos-Gómez, Kazunori Fujisawa, Morinobu Endo, Olga Martin Cadiz, Juan Baselga Llido, Mauricio Terrones Hydrogen peroxide (H2O2) is an alternative oxidant and green method for the purification and functionalization of carbon nanotubes (CNTs), which works more efficiently in combination with UV radiation. In this paper, we investigated and monitored the oxidation mechanism of ethanol-synthesized and standard multi-walled carbon nanotubes. Characterization was carried out by high-resolution transmission electron microscopy (HRTEM), X-ray photo electron spectroscopy (XPS), acid/base titrations, thermo-gravimetric analysis (TGA) and Raman spectroscopy. Interestingly, we found a close correlation between oxidation time and the nature of the nanotubes. For the first time, a unique cyclic peeling of layers within MWNTs, termed “onion effect” was found. In this process, the degree of crystallinity of the outer layers significantly changed for the different peeling stages. We explain the process and how the number of layers within nanotubes gradually decreases when reaching critical acid concentrations. This method now allows the synthesis of MWCNTs with specific numbers of walls, diameter and controlled degree of crystallinity that could be effectively used for applications in biology and composites.Graphical abstractImage 1
       
  • Scalable preparation of graphene reinforced Zirconium diboride composites
           with strong dynamic response
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Baoxi Zhang, Laifei Cheng, Yunchao Lu, Qiang Zhang An imperative bottleneck of ceramic materials with weak dynamic response, associating with rigid covalent or ionic bonds, has restricted its extensively applications. Despite traditional reinforcements of carbon fibers or whiskers improved their dynamic response, it was still limited to a threshold owing to their heterogeneous dispersion and structural damage. Graphene has been regarded as an alternative reinforcement due to its excellent in-plane mechanical property. Here we developed a scalable process of chemical assembly to fabricate ZrB2-SiC/graphene composites. Graphene offered a shielding effect to arrest crack propagation, and ultimately restrained fracture and fragmentation of composites. Compared with pristine ZrB2-SiC composites, the dynamic strain of ZrB2-SiC/graphene composites (5.2 vol %) depicted a 138% increasing (from 0.095 to 0.226%), and their dynamic stress exhibited a 28% increasing (from 1.50 to 1.92 GPa). This work offers a paradigm for preparing graphene reinforced ceramic composites with strong dynamic response.Graphical abstractImage
       
  • Amorphous graphene – Transformer oil nanofluids with superior thermal
           and insulating properties
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Mississippi Missouri Bhunia, Karamjyoti Panigrahi, Swati Das, Kalyan Kumar Chattopadhyay, Paramita Chattopadhyay Nanofluids has emerged as a prominent and promising substitution of liquid dielectrics in industrial applications. Nevertheless, their sedimentation has been a consequential stumbling block for extensive and effective exploitation. Present work reports, stable, surfactant free and dilute homogeneous dispersion of a novel 2D dielectric nanomaterial: “Amorphous Graphene Sheets” (a-GS; with high ID/IG ratio), in transformer oil (TO) at lower nanofiller (0.0012–0.01 wt %) concentration. Nanofluids smartly address the much needed efficient thermal and electrical management with high resistivity and low loss compared to base oil. Persistent and high degrees of enhancement in the breakdown strength (40%) is observed. The electric double layer (EDL) development and prompted polarization (under electric stress), of the material leads to efficient charge trapping and de-detrapping in non-localized states. This phenomena uplifts the breakdown voltage and other electrical parameters than base TO. Lattice vibration of nanostructure along with EDL and cluster formation explains thermal transport phenomena at the nanoscale. Whereas confirmation of superior heat conduction by a-GS NFs were obtained by surface imaging and systematic study of spatial heat flow distribution. Hence the proposed hybrid nanofluid holds great promise for utilizing in the field of high voltage electrical insulation application.Graphical abstractImage 1
       
  • Polyurethane/carbon fiber composite tubular electrode featuring
           three-dimensional interpenetrating conductive network
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Kailin Zhang, Yijun Li, Huan Zhou, Min Nie, Qi Wang, Zhengkun Hua Flexible and stretchable electronics are important components in medical implantation, wearable durable devices and so on. However, conductive stability often conflicts with the mechanical stretchability in terms of decreased conductivity from the deformation. Here, we proposed a facile and effective strategy to construct a three-dimensional interpenetrating alignment configuration of conductive carbon fibers (CFs) during polyurethane (PU) tube extrusion by manipulating opposite-helical flows. With the benefits of the 3D-overlapping conductive network, the as-fabricated PU composite tubes were superior to convention-extruded ones with axial-flow driven 2D parallel-aligned configuration, with regard to higher initial conductivity, exceptional electrical stability under high strain, as well as excellent electrical reversibility in cycle loadings. The underlying working mechanism responding to mechanical deformation was well-established based on the transformation from contract conduction to tunneling one. As a promising practice application, the potential of the novel composite tube applied to thermal therapy was explored and it demonstrated that the composite tubes could produce high heating energy with characteristics of fast thermal response, low operation voltage and high stability under mechanical disturbance, via effective electric-thermal conversion. Accordingly, conductive stability-stretchability dilemma in the conventional stretchable electrode could be solved via simple one-step melt-process suitable for mass production.Graphical abstractImage
       
  • Controllable actuation of photomechanical bilayer nanocomposites for
           in vitro cell manipulation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Weitao Jiang, Dong Niu, Lanlan Wei, Guoyong Ye, Lanlan Wang, Hongzhong Liu, Ping Chen, Feng Luo, Bingheng Lu Mechanotransduction enables cells to translate external forces and physical constraints into biochemical signals controlling multiple aspects of cell behavior. Methodologies mimicking various mechanical and biomedical forces exposed to cells, have been proposed to investigate cell mechanotransduction. However, it is still a great challenge developing platform towards dynamically multivariate mechanical stimulation addressing individual cells or small colonies of cells. A photomechanical and biocompatible platform for extracellular mechanical stimuli is constructed by soft bilayer nanocomposites composed of polydimethylsiloxane (PDMS) and PDMS/GNPs (graphene nanoplatelets). The fast backlash bending process can give rise to mechanical stimuli to the cells growing on it in a controllable manner by near infrared (nIR) irradiation. Beneficial from the excellent controllability in nIR light intensity and working frequency, the backlash bending velocity, acceleration, frequency, as well as sophisticated bending process can be well controlled, thus extracellular mechanical forces even predesigned loading cycles can be realized. SGC-7901 cells viability, one of the lines in highest incidence Gastric cancer in almost Asian countries, can be restricted by our proposed platform. It will not only provide a solution for studying cell mechanotransduction with more complicated force conditions, but also demonstrate a promising methodology supplementing the physical therapy for fighting against the malignant tumor.Graphical abstractPhotomechanical soft bilayer was proposed for in vitro cell manipulation. Controllable mechanical forces can be realized beneficial from nIR light.Image 1
       
  • Mechanism of SiOx particles formation during CVD graphene
           growth on Cu substrates
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Xiaoming Ge, Yanhui Zhang, Lingxiu Chen, Yonghui Zheng, Zhiying Chen, Yijian Liang, Shike Hu, Jing Li, Yanping Sui, Guanghui Yu, Zhi Jin, Xinyu Liu For graphene grown on Cu substrate via chemical vapor deposition (CVD), numerous nanometer particles are distributed along the graphene grain boundaries or evenly on the circumjacent substrate surface. The particles form new nucleation centers of graphene or destroy the graphene membrane during growth. In order to clarify the origin of particles, the formation process was studied by etching graphene at high temperature with different atmospheric pressures. We demonstrated that the formation of the particles is closely related to the competition of hydrogen and oxygen during growth; we also confirmed that the main component of particles was SiOx by energy dispersive spectrometry (EDS) measurement in transmission electron microscopy (TEM). Finally, on the basis of the formation mechanism, we proposed efficient approaches to reduce SiOx particles that improve the quality of graphene during actual CVD preparation process.Graphical abstractImage 1
       
  • Comparative study of shortening and cutting strategies of single-walled
           and multi-walled carbon nanotubes assessed by scanning electron
           microscopy
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Magdalena Kierkowicz, Elzbieta Pach, Ana Santidrián, Stefania Sandoval, Gil Gonçalves, Ester Tobías-Rossell, Martin Kalbáč, Belén Ballesteros, Gerard Tobias Short carbon nanotubes (CNTs) are desired for a variety of applications. As a consequence, several strategies have been reported to cut and shorten the length of as-produced CNTs via chemical and physical routes. The efficiency of a given strategy largely depends on the physico-chemical characteristics of the CNTs employed. In order to be able to directly compare the advantages and disadvantages of commonly used protocols, a single batch of chemical vapor deposition single-walled CNTs (SWCNTs) and a batch of multi-walled CNTs (MWCNTs) were subjected to four cutting/shortening strategies, namely acid cutting, piranha treatment, steam shortening and ball milling. The length distribution was assessed by means of scanning electron microscopy. Sample purity and CNT wall structure were determined by Raman spectroscopy, thermogravimetric analysis and magnetic measurements. Within the employed experimental conditions, piranha treatment turned out to be the most efficient to achieve short SWCNTs with a narrow length distribution in a good yield, whereas a mixture of sulfuric/nitric acid was preferred in the case of MWCNTs. A subsequent short steam treatment allowed to remove functional groups present in the samples, leading to median length distributions of 266 nm and 225 nm for SWCNTs and MWCNTs respectively after the combined protocols.Graphical abstractImage 1
       
  • Achieving high strength and ductility in graphene/magnesium composite via
           an in-situ reaction wetting process
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Miao Wang, Yu Zhao, Li-Dong Wang, Yun-Peng Zhu, Xiao-Jun Wang, Jie Sheng, Zi-Yue Yang, Hai-Long Shi, Zhen-Dong Shi, Wei-Dong Fei The dispersibility and interfacial wettability are two essential requirements for fabricating graphene/metal composites with high performance. However, the simultaneous improvement of dispersibility and wettability between the graphene and metal matrix is still a challenge. Herein we attempted to improve the dispersibility, interfacial wettability and mechanical properties of graphene/magnesium composites via an in-situ reaction wetting process. Graphene oxide (GO) was modified with ZnO coating by a coprecipitation route, and the composites were fabricated by an ultrasonic assisted stir casting method. The composites showed a microstructure with homogeneous dispersion of graphene in the matrix. Compared with unreinforced Mg matrix, the composites demonstrated an exceptional and joint improvement in yield strength, hardness, and good ductility. Microstructural examinations revealed that the molten Mg could react with ZnO coating and form an interfacial product composed of MgO during the composite fabrication. The interfacial in-situ reaction could facilitate interfacial wetting and the interfacial product MgO could improve the interfacial bonding between graphene and matrix. The grain-size refinement and load transfer provided by graphene were the two main strengthening mechanisms in the composite. This study provides new insights into the interfacial design of advanced graphene/metal composites with exceptionally high strength and ductility.Graphical abstractImage 1
       
  • Designing an interlayer of reduced graphene oxide aerogel and
           nitrogen-rich graphitic carbon nitride by a layer-by-layer coating for
           high-performance lithium sulfur batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Juthaporn Wutthiprom, Nutthaphon Phattharasupakun, Montree Sawangphruk Herein, reduced graphene oxide aerogel (GA) with 3D interconnected conductive and porous structure was used as a host of sulfur (S@GA cathode). GA was also used together with nitrogen-rich graphitic carbon nitride (GCN) as the interlayer accommodating the soluble lithium polysulfides (LPSs). The interlayer was fabricated by a layer-by-layer coating technique on the flexible and processible carbon fiber paper (CFP) substrate. The interlayer inserted between the cathode and the separator provides a strong lithium polysulfide adsorptivity. Adsorptive LPS species on the interlayer were also investigated by an ex situ X-ray photoelectron spectroscopy. After finely tuned, the as-fabricated LSB using the S@GA cathode with the GA/GCN interlayer exhibits 75% higher specific capacity than the cell without interlayer. It has a low capacity fading of 0.056% per cycle after tested for 800 cycles. Our new design and configuration of LSB may practically be used in high-energy applications since it can effectively address many issues of the current LSBs.Graphical abstractImage 1
       
  • Oxidation limited thermal boundary conductance at metal-graphene interface
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): David B. Brown, Thomas L. Bougher, Baratunde A. Cola, Satish Kumar Thermal management is a substantial challenge in high-power-density micro- and nanoelectronic devices, and the thermal resistance at the interfaces in these devices is a major bottleneck to heat removal. Graphene has emerged as a potential candidate for next generation nanoelectronic devices because of its exceptional transport properties; however, the thermal interaction between graphene and other materials such as metals is not completely understood. Here we report thermal boundary conductance (TBC) measurements at metal-graphene-metal (M-G-M) interfaces at room temperature using time-domain thermoreflectance. The metals used in this study represent two classes based on the type of bonding formed with graphene. Ti and Ni form chemisorbed interfaces (strong bonding) with graphene and high TBC is expected while Au forms physisorbed interfaces (weak bonding). The measured TBC at M-G-M interfaces showed little variation (∼30 MW/m2-K) and was similar to metal-graphene-SiO2 interfaces, contrary to high TBC predicted by previous simulation studies. X-ray photoelectron spectroscopy was used to estimate thickness of the native oxide layer of bottom Ti (2.8 nm) and Ni (2.5 nm) layers. The conductance of these thin native oxide layer was much greater than the overall TBC but prevented formation of chemisorbed interfaces between graphene and metal for Ti and Ni cases leading to significantly lower TBC and highlighting an important consideration for practical applications.Graphical abstractImage 1
       
  • The threshold displacement energy of buckminsterfullerene C60 and
           formation of the endohedral defect fullerene He@C59
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Mark H. Stockett, Michael Wolf, Michael Gatchell, Henning T. Schmidt, Henning Zettergren, Henrik Cederquist We have measured the threshold center-of-mass kinetic energy for knocking out a single carbon atom from C60− in collisions with He. Combining this experimental result with classical molecular dynamics simulations, we determine a semi-empirical value of 24.1±0.5 eV for the threshold displacement energy, the energy needed to remove a single carbon atom from the C60 cage. We report the first observation of an endohedral complex with an odd number of carbon atoms, He@C59−, and discuss its formation and decay mechanisms.Graphical abstractImage 1
       
  • Nitrogen-doped graphene-based catalyst with metal-reduced organic
           framework: Chemical analysis and structure control
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Shiqiang Zhuang, Harsimranjit Singh, Bharath Babu Nunna, Debdyuti Mandal, J. Anibal Boscoboinik, Eon Soo Lee Here we report an advanced nitrogen-doped graphene-based catalyst with metal-reduced organic framework structure (N-G/MOF) prepared by functionalizing ZIF-8 and nitrogen-functionalized graphene oxide using the nanoscale high energy wet ball milling method. The chemical structure control of N-G/MOF was studied by characterizing the variation of the chemical structure of synthesized samples throughout targeted grinding speeds. The results proved that the chemical interaction between ZIF-8 and N-G caused the reduction of nitrogen, oxygen and zinc atoms, and the variation of chemical bonding composition in N-G/MOF. The reduction rate of zinc was gradually increased with the increasing grinding speed and reached 82% of zinc loss at 650 RPM. The characterization of carbon and nitrogen bonding composition confirmed that the reduction of nitrogen, oxygen and zinc atoms was caused by the decomposition of C-N-Zn heteroatom contents in ZIF-8 and the O-containing functional groups in N-G which were influenced by the grinding speed. The decomposition of ZIF-8 not only affected the framework and the pore structure but also modified the chemical structure and the surface distribution of C-N-containing functional groups-constituted active sites. The variation of physical and chemical properties enhanced the electrochemical performance of N-G/MOF and made it comparable to the 10 wt% Pt/C catalyst.Graphical abstractImage 1
       
  • Ultrathin HfO2-modified carbon nanotube films as efficient polysulfide
           barriers for Li-S batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Weibang Kong, Datao Wang, Lingjia Yan, Yufeng Luo, Kaili Jiang, Qunqing Li, Li Zhang, Shigang Lu, Shoushan Fan, Ju Li, Jiaping Wang Ultrathin and cross-stacked carbon nanotube (CNT) films modified with hafnium oxide (HfO2) by atomic layer deposition are employed as efficient polysulfide barriers for high performance Li-S batteries. A HfO2/CNT interlayer has an ultrathin, flexible structure with a thickness of 1.5 μm and an areal density of 0.087 mg cm−2, along with excellent wettability to electrolyte. The highly conductive CNT network and the catalytic surface adsorption of polysulfide species by HfO2 significantly suppress the polysulfides shuttling phenomenon. With high sulfur loadings of up to 75 wt%, electrodes incorporating a HfO2/CNT interlayer show noticeable improvements in various electrochemical properties, including long-term cycling stability (721 mA h g−1 after 500 cycles at 1 C), high rate performance (800 mA h g−1 at 5 C), favorable anti-self-discharge capabilities, and suppression of Li anode corrosion. These results suggest a new and efficient polysulfide trapping material and a viable configuration for high-performance Li-S batteries.Graphical abstractAn ultrathin HfO2/CNT interlayer is used as an efficient polysulfide barrier to improve the performance of Li-S batteries.Image 1
       
  • Laser-induced graphene synthesis of Co3O4 in graphene for oxygen
           electrocatalysis and metal-air batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Muqing Ren, Jibo Zhang, James M. Tour We present here a straightforward synthesis of highly efficient bifunctional OER/ORR catalysts through a facile laser-induced graphene (LIG) process to produce Co3O4/LIG. The Co3O4/LIG showed OER and ORR activity comparable to noble metal-based catalysts in alkaline electrolyte. Furthermore, the Co3O4/LIG exhibited promising performance in Zn-air and Li-O2 batteries. The rechargeable Zn-air battery has an open-circuit potential of 1.46 V and a high power density of 84.2 mW/cm2 at 100 mA/cm2. The Li-O2 battery with the Co3O4/LIG cathode exhibits low overpotentials in both charge and discharge processes and excellent cycling stability up to 242 cycles.Graphical abstractImage 1
       
  • Insight of the effect of graphitic cluster in the performance of carbon
           aerogels doped with nickel as electrodes for supercapacitors
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Abdalla Abdelwahab, Jesica Castelo-Quibén, María Pérez-Cadenas, Francisco J. Maldonado-Hódar, Francisco Carrasco-Marín, Agustín F. Pérez-Cadenas A series of Ni-doped carbon aerogels with different Ni loadings were prepared and extensively characterized from a textural, chemical and electro-chemical point of view. The formation of graphitic clusters on nickel particles was specially analysed by XPS and Raman spectroscopy. Electro-capacitive properties were studied by cyclic voltammetry, chronopotentiometry, and electrochemical impedance spectroscopy in a three and two-electrode cell, and in acidic media and non-aqueous aprotic electrolyte.The use of Ni as a polymerization catalyst slightly decreases the micropore volume of the carbon aerogels but on the contrary, a great increase in their mesopore volume was obtained. All samples present high gravimetric capacitances, ranging from 182 to 219 F g−1 in 1 M H2SO4, and from 49 to 63 F g−1 in 1 M tetraethylammonium tetrafluoroborate. Results show that the equivalent series resistances decrease as the Ni content increases and the capacitance increases in the same sense. This trend is directly related to the presence of a good developed mesopore network in Ni-doped carbon aerogels and a better electrical conductivity due to the formation of the graphitic clusters around the Ni particles. The stability of the charge-discharge cycles, studied by floating tests, showed a very good performance of the doped-carbon aerogels.Graphical abstractImage
       
  • Synergism of nitrogen and reduced graphene in the electrocatalytic
           behavior of resorcinol - Formaldehyde based carbon aerogels
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Balázs Nagy, István Bakos, Imre Bertóti, Andrea Domán, Alfréd Menyhárd, Miklós Mohai, Krisztina László Graphene oxide (GO) containing resorcinol – formaldehyde and resorcinol – formaldehyde – melamine polymer aerogels were converted to carbon aerogels in order to study the cooperative effect of the reduced GO and nitrogen functionalities on the electrochemical behavior of carbon aerogels. The morphology of the carbon gel was characterized by scanning and transmission electron microscopy, and low temperature nitrogen adsorption/desorption. X-ray photoelectron spectroscopy was used to study their surface chemistry. The thermal behavior was investigated by thermogravimetric analysis. The electrochemical performance was tested with cyclic- and linear sweep voltammetry (CV and LSV, respectively). The final N content was ca 1 atomic%. The nitrogen atoms are in a C=N-C type chemical environment or replace a carbon atom in the graphene-like layer. Either N or the reduced GO enhance the activity in oxygen reduction reaction. When both are present in the matrix the dominant reduction pathway changes from the slow 2e− to the more efficient 4e− route. It is also probable that the in-situ formed H2O2 improves the wettability of the basically hydrophobic carbon surface and increases the electrochemically active surface.Graphical abstractImage 1
       
  • Water-selective adsorption sites on detonation nanodiamonds
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Elda-Zoraida Piña-Salazar, Radovan Kukobat, Ryusuke Futamura, Takuya Hayashi, Sakai Toshio, Eiji Ōsawa, Katsumi Kaneko Nanodiamond particles form aggregates having porosity in the range of micropores to mesopores with an average pore diameter of 4.5 nm. The measured porosity depends on the removal of pre-occupied water and gases from the nanodiamond aggregates, which is sensitive to thermal treatments. We heated hydrogel nanodiamonds at 423–623 K in vacuo in order to understand the relationship between water adsorptivity and pore structure evaluated from nitrogen and argon adsorption isotherms at 77 K and 87 K, respectively. Temperature-programmed evolved gas analysis showed the evolution of water and CO2 on heating nanodiamonds in vacuo up to 700 K. The surface functional groups of nanodiamonds were not affected by the thermal treatments, as shown by FTIR and XPS analyses. However, the water adsorptivity was enhanced by heating at 623 K due to the removal of the pore blocking effect originated from water molecules selectively adsorbed. Water molecules adsorbed on these selective sites should cause the intensive hygroscopic property of nanodiamonds.Graphical abstractImage 1
       
  • Dry microwave heating enables scalable fabrication of pristine holey
           graphene nanoplatelets and their catalysis in reductive hydrogen atom
           transfer reactions
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Keerthi Savaram, Mengjun Li, Kentaro Tajima, Kazuyuki Takai, Takuya Hayashi, Gene Hall, Eric Garfunkel, Vladimir Osipov, Huixin He Current approaches for scalable production of holey graphene materials require graphene oxide or reduced graphene oxide as starting materials. The molecular basis fundamentally determines that the holey graphene materials thus generated still contain a large number of defects on their basal planes. The existence of these defects not only complicates fundamental studies but also influences practical applications due to the significance decrease in their conductivity and chemical stability. This work exploits microwave chemistry to enable rapid mass production of holey graphene nanoplatelets with their basal plane nearly intact. Interestingly, the unique chemistry also begets the generated nanoholes with edges rich in zigzag geometry. The near-pristine nature of the basal planes and the zigzag edges were clearly observed via atomic resolution TEM and further supported by the localized π-edge states studied via electron paramagnetic resonance (EPR) measurements. The holey graphene nanoplatelets were explored as metal free catalysts for hydrogen atom transfer reactions. These unique holey graphene nanoplatelets exhibited excellent catalytic activity, desired selectivity, and chemical stability for recyclability, which were not achievable by their counterpart holey graphene derivatives with basal plane defects.Graphical abstractImage 1
       
  • N, P (S) Co-doped Mo2C/C hybrid electrocatalysts for improved
           hydrogen generation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Dezhi Wang, Tianying Liu, Junchao Wang, Zhuangzhi Wu Recently, molybdenum carbide (Mo2C) has aroused tremendous interests as a potential candidate to replace Pt-based electrocatalysts for hydrogen evolution reaction (HER). However, the HER performance of Mo2C is intrinsically limited by the empty d-orbitals with a large density in Mo2C and the resulting strong Mo-H bonding. Heteroatom-doping is an effective route for tuning the d-orbitals of Mo2C and improving the catalytic activity. Hence, in this work, we design two facile pathways to synthesize unique N, P and N, S dual-doped Mo2C/C hybrid electrocatalysts as highly active HER catalysts. The co-doping of N, P and N, S involves the substitute of C atoms in both Mo2C crystals and carbon matrix for a better synergistic effect, and can further improve the HER activity of Mo2C electrocatalysts compared to individual N doping. As expected, the obtained N, P or N, S dual-doped Mo2C catalyst (NP-Mo2C or NS-Mo2C) exhibits lower electrochemical resistance, higher intrinsic activity of each active site, or larger electrochemically active surface area (AECSA, for NP-Mo2C), thus leading to enhanced HER activity as well as stability in the acidic solution.Graphical abstractImage 1
       
  • Nanostructured carbon materials for enhanced nitrobenzene adsorption:
           Physical vs. chemical surface properties
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Archi Dasgupta, Juan Matos, Hiroyuki Muramatsu, Yuji Ono, Viviana Gonzalez, He Liu, Christopher Rotella, Kazunori Fujisawa, Rodolfo Cruz-Silva, Yoshio Hashimoto, Morinobu Endo, Katsumi Kaneko, Ljubisa R. Radovic, Mauricio Terrones The influence of physical and chemical surface properties on the adsorption of nitrobenzene, a major organic contaminant in wastewater, was investigated using a wide range of graphene-based materials. These included carbon blacks and activated carbons as well as nanostructured materials such as graphitic nanoribbons (GNRs) and graphene-like structures derived from rice husk (RHC). The surface of GNRs was also modified by oxidation with hydrogen peroxide under UV irradiation (yielding Ox-GNRs). For the understanding of the importance of electrostatic and dispersive interactions, the uptake of nitrobenzene was measured in solutions at controlled pH conditions. The Langmuir and Freundlich parameters were found to be dependent on both surface physics and chemistry. To elucidate this influence, the adsorption of H2O/D2O was performed on selected samples. The edge surfaces of nanoporous carbons appear to be exert dominant interactions with polar molecules such as nitrobenzene. At the same time, while the presence of micropores is the most important factor for adsorption at low concentration, the meso- and macropores become more important at higher nitrobenzene concentrations. The novelty of this study resides in the use of complementary techniques designed to understand the adsorption on traditional carbon materials as a guide for the optimization of novel, graphene-like nanostructured adsorbents.Graphical abstractImage 1
       
  • Step-by-step self-assembly of 2D few-layer reduced graphene oxide into 3D
           architecture of bacterial cellulose for a robust, ultralight, and
           recyclable all-carbon absorbent
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Honglin Luo, Jing Xie, Jie Wang, Fanglian Yao, Zhiwei Yang, Yizao Wan Development of high performance absorbents is of particular importance in environmental protection. Herein, we report a mechanically robust, ultralight, and recyclable absorbent with highly dispersed two-dimensional (2D) few-layer reduced graphene oxide (FrGO) in a three-dimensional (3D) carbonized bacterial cellulose (CBC) monolith via a novel step-by-step in situ biosynthesis (SBSB) method followed by carbonization. The step-by-step self-assembly produces a mechanically entangled nanostructure between FrGO and CBC nanofibers. The self-assembled CBC/FrGO nanocomposite absorbent possesses multi-scaled pores and large specific area. When used as absorbents, the monolithic CBC/FrGO aerogel exhibits excellent recyclability and high absorption capacities toward numerous oils and organic solvents. These properties, together with the green, cost-effective and scalable production process, make it very promising as a superior all-carbon absorbent for environmental protection.Graphical abstractImage 1
       
  • Defying Coulomb's law: A lattice-induced attraction between lithium ions
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Fernanda Juarez, Fabiola Dominguez-Flores, Aleksej Goduljan, Leila Mohammadzadeh, Paola Quaino, Elizabeth Santos, Wolfgang Schmickler Normally ions with the same charge repel each other, but in very rare cases an intervening medium can produce an apparent attraction. We have studied the adsorption of Li-ions on semiconducting carbon nanotubes by density functional theory, one ion being inside, the other outside. The tube shields the direct Coulomb interaction between the ions, but the presence of the ion inside facilitates the adsorption of the ion outside, thus producing an apparent attraction. We give a quantitative explanation based on the electronic band structure of the tube, and surmise, that the same effect will hold on other carbon materials. Our results may explain the apparent attraction of Li-ions that has been observed in Li-batteries.Graphical abstractImage 1
       
  • Carbon nanotube attached subwavelength grating for broadband terahertz
           polarization conversion and dispersion control
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Shi-Tong Xu, Sai Chen, Lin-Lin Mou, Fei Fan, Zun-Feng Liu, Sheng-Jiang Chang Carbon nanotube (CNT), as a recently emerged newfangled nanomaterial, has been applied in terahertz (THz) polarizer due to its anisotropic hyper-ordered orientation. Herein, we simply adhere two orthogonal CNT sheets to the both sides of dielectric subwavelength grating to form a compound structure (i.e. CNT@Grating). Due to the subwavelength integration and cavity modes, the CNT@Grating presents local resonances between two CNT sheets, which greatly enhances the polarization rotation and expands the bandwidth. Compared with the large phase shift dispersion of single subwavelength grating, its phase shift dispersion and impedance can be manipulated by adjusting the layer number of CNT, and finally a broadband close zero dispersion from 0.4 to 0.95 THz has been obtained, which leads to a broadband THz polarization conversion. This work provides a new design idea towards practical applications for THz broadband polarization conversion and dispersion control.Graphical abstractWe proposed a broadband THz linear polarization convertor, which integrated with the dielectric grating and CNT (CNT@Grating). Here, CNT plays a role of polarizer like the commercial metal wire grid and dielectric grating has a large birefringence that can employ as artificial wave-plate.Image 1
       
  • Diamond nanothread-based 2D and 3D materials: Diamond nanomeshes and
           nanofoams
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Julian F.R.V. Silveira, Andre R. Muniz Diamond nanothreads (DNTs) are one-dimensional, fully sp3-bonded carbon nanostructures resulting of covalent bonding between stacked benzene molecules in a crystal, induced by application of high pressure, as demonstrated in experiments. In this work, we used classical Molecular Dynamics simulations to propose the synthesis of analogous two- and three-dimensional porous nanostructures, which we named diamond nanomeshes (DNM) and diamond nanofoams (DNF), consistently to the definition of DNTs, and computed some of their structural and mechanical properties. Two different approaches toward creation of such materials are proposed. One of them consists in interconnecting finite domains of conventional DNTs, achieved through partial surface dehydrogenation and subsequent C-C covalent bonding. The other approach considers that the formation of sp3 C-C bonds between stacked benzene molecules under high pressure could be extended to polycyclic aromatic hydrocarbon (PAH) molecules, generating crosslinked DNT-like structures. Different atomic configurations can be achieved by varying the morphology of DNTs used in their construction, the PAH molecules, and the nature of the DNT covalent interconnections. The resulting materials exhibit an interesting combination of mechanical strength, flexibility, lightness, high porosity and high specific surface area, enabling potential applications in reinforced nanocomposites, gas storage/separation, sensors, among others.Graphical abstractImage 1
       
  • On the mechanical properties of novamene: A fully atomistic molecular
           dynamics and DFT investigation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Eliezer Fernando Oliveira, Pedro Alves da Silva Autreto, Cristiano Francisco Woellner, Douglas Soares Galvao We have investigated through fully atomistic reactive molecular dynamics and density functional theory simulations, the mechanical properties and fracture dynamics of single-ringed novamene (1R-novamene), a new 3D carbon allotrope structure recently proposed. Our results showed that 1R-novamene is an anisotropic structure with relation to tensile deformation. Although 1R-novamente shares some mechanical features with other carbon allotropes, it also exhibits distinct ones, such as, extensive structural reconstructions. 1R-novamene presents ultimate strength (∼100 GPa) values lower than other carbon allotropes, but it has the highest ultimate strain along the z-direction (∼22.5%). Although the Young's modulus (∼600 GPa) and ultimate strength values are smaller than for other carbon allotropes, they still outperform other materials, such as for example silicon, steel or titanium alloys. With relation to the fracture dynamics, 1R-novamene is again anisotropic with the fracture/crack propagation originating from deformed heptagons and pentagons for x and y directions and broken sp3 bonds connecting structural planes. Another interesting feature is the formation of multiple and long carbon linear chains in the final fracture stages.Graphical abstractImage 1
       
  • Thermally activated double-carrier transport in epitaxial graphene on
           vanadium-compensated 6H-SiC as revealed by Hall effect measurements
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Tymoteusz Ciuk, Andrzej Kozlowski, Pawel Piotr Michalowski, Wawrzyniec Kaszub, Michal Kozubal, Zbigniew Rekuc, Jaroslaw Podgorski, Beata Stanczyk, Krystyna Przyborowska, Iwona Jozwik, Andrzej Kowalik, Pawel Kaminski In this report we demonstrate the results of charge carriers transport studies in graphene using a Hall effect sensor fabricated on quasi-free-standing monolayer graphene grown on a semi-insulating on-axis vanadium-compensated 6H-SiC(0001) substrate in an epitaxial Chemical Vapor Deposition process. The sensor is passivated with aluminum oxide through atomic layer deposition and offers current-mode sensitivity of 140 V/AT with thermal stability of − 0.02%/K within the range between 80 and 573  K. The electrical properties of the graphene layer are determined as a function of temperature ranging from 300 to 770  K. High-temperature characteristics of passivated and not passivated graphene are compared and their profiles explained through a double-carrier transport involving the spontaneous-polarization-induced holes in the graphene layer and the thermally activated electrons from a shallow donor level of nitrogen in the quasi-cubic (k1) site and a deep acceptor level of vanadium in the hexagonal (h) site both present in the bulk of the vanadium-compensated SiC substrate. Finally, we conclude that this mechanism is directly responsible for the limitation of the thermal stability of the sensor's current-mode sensitivity.Graphical abstractImage 1
       
  • Channelling and induced defects at ion-bombarded aligned multiwall carbon
           nanotubes
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Giulio D'Acunto, Francesca Ripanti, Paolo Postorino, Maria Grazia Betti, Mattia Scardamaglia, Carla Bittencourt, Carlo Mariani A detailed investigation of ion channelling and defect production for a highly-ordered array of multi-wall carbon nanotubes is presented. The effects of argon ion bombardment (0.25–5 keV) carried out either parallel (top) or perpendicular (side) to their axis, have been studied by Raman, X-Ray Photoelectron Spectroscopy and Scanning Electron Microscopy. Raman spectra provided evidence of channelling of the Ar+ ions observed for top bombardment along the whole 180 μm carbon nanotube length, while the penetration length is limited to the first 10 μm when the ions impinge from the side. The nature of defects, determined through the spectral fingerprints of the C 1s core level as a function of energy and flux, unveils a distorted sp3-like bonding increase and the π-excitation decrease till quenching. Dangling bond states due to displaced carbon atoms become significant only at beam energies higher than 0.25 keV and high flux. These results on anisotropic channelling and selective defects creation open new perspectives in the application of highly-ordered arrays of multi-wall carbon nanotubes as anisotropic detectors.Graphical abstractImage 1
       
  • Designed fabrication of reduced graphene oxides/Ni hybrids for effective
           electromagnetic absorption and shielding
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Wei Xu, Guang-Sheng Wang, Peng-Gang Yin Reduced graphene oxide (rGO)/Ni hybrids with different mass ratio are successful synthesized in order to tune the microwave absorption together with the electromagnetic shielding performance. By properly adjusting the permittivity and permeability derived from different contents of the rGO and Ni, an rGO/Ni composite with excellent microwave absorption properties is obtained. An optimal reflection loss value of −39.03 dB at 13 GHz is achieved for the composite with rGO/Ni ratio of 1:1, and the bandwidth less than −10 dB can reach up to 4.3 GHz (from 11 to 15.3 GHz) with a thickness of 2.0 mm. Furthermore, the composite with rGO/Ni ratio of 4:1 shows superior electromagnetic shielding performance as high as 52 dB, which far surpasses the best value for most carbon-based materials. Fundamental mechanisms for absorbing and shielding performance are discussed.Graphical abstractImage 1
       
  • MnO-encapsulated graphene cubes derived from homogeneous MnCO3-C cubes as
           high performance anode material for Li ion batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Zhihua Xiao, Guoqing Ning, Xinlong Ma, Wei Li, Chunming Xu Nanocomposites containing high capacity anode materials (such as Si, Sn or transition metal oxides) and carbon matrix, are widely studied to obtain high performance anodes for Li ion batteries (LIBs). However, these nanocomposites often suffer from low structural stability and high irreversible Li storage. Here, MnO-encapsulated graphene cubes are produced by calcination of homogeneous MnCO3-C composite cubes. The cubic graphene shells provide high conductivity and excellent structural stability to the MnO cores, and the high calcination temperature of 1200 °C can significantly reduce the specific surface area of the MnO@graphene cubes and thus reduce their irreversible capacity. The MnO@graphene cubes exhibit high Li storage capacity (1092 mAh g−1 at 50 mA g−1 and 790 mAh g−1 at 500 mA g−1) at a voltage platform ∼ 1 V, superior rate capability (586 mAh g−1 at 1000 mA g−1) and excellent long term cycling performance (undiminished after 500 cycles). Our results provide a useful method to design high performance graphene-based anode composites for LIBs.Graphical abstractImage 1
       
  • Structure-directed fabrication of ultrathin carbon nanosheets from layered
           metal salt: A separation and supercapacitor study
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Hongliang Lyu, Jikui Zhu, Bihang Zhou, Haifei Cao, Jingui Duan, Lingyun Chen, Wanqin Jin, Qiang Xu Ultra-thin carbon nanosheets showed specific and promising applications in energy conversions and mass transfers. Inspired by the idea of structure-directed formation, we report a catalyst-free, self-templated, eco-friendly, controllable and facile method for the preparation of high porous and ultrathin two dimensional carbon materials via in-situ thermal transformation of crystalline and layered metal-salt. The conversion mechanism was clearly validated, while the crystallization degree of graphitic carbon of series of nanosheets was systemically tuned. The hierarchical pore system enables the carbon nanosheets to show the N2 gas uptake up to 1780 cm3 g−1 and pore volume to 2.7 cm3 g−1. With in-situ generated carboxylate and singly-bonded oxygen, the C-600 showed highest C3H6/C2H4 gas selectivity (16.0) among all porous materials. More importantly, complete removal of C3H6 from its C2H4 mixture was confirmed by breakthrough experiments under flowing condition at ambient temperature. As well, due to the higher surface area, the symmetric supercapacitor device that assembled from C-600 showed excellent cycling durability (98.3%) with energy density of 18.39 Wh·kg−1 during ultrafast charging/discharging 10000 cycles.Graphical abstractImage 1
       
  • Direct synthesis of high-quality nitrogen-doped graphene via ion
           implantation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Yunbiao Zhao, Xu Wang, Engang Fu, Dong Han, Peipei Wang, Zaoming Wu, Yi Chen, Yuhan Chen, Ziqiang Zhao Synthesis of nitrogen-doped graphene (NG) is of great importance and conventional synthesis methods still remain huge challenges due to uncontrollable nitrogen doping content and complicated experimental procedure. In this study, a promising approach for synthesis of high-quality NG via nitrogen ion implantation compatible with the current microelectronic industry is reported. By nitrogen ion implantation into a newly designed multilayered substrate (Ni/Cu/amorphous-SiC/SiO2/Si), high-quality NG can be directly grown on the metal surface after a one-step rapid thermal processing. A detailed growth model of NG based on the design of multilayered substrate, the low energy ion implantation and the formation of Cu-Ni alloy with composition gradient is established. The ion implantation approach could open up a new pathway for doping graphene, as well as shed light on versatile and potential applications of doping other 2D materials.Graphical abstractImage 1
       
  • Dehalogenated carbon-hosted cobalt-nitrogen complexes for high-performance
           electrochemical reduction of oxygen
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Gang Dou, Kewen Du, Qidong Dang, Xiangchao Chen, Xin Zhang, Mei Guo, Yaqun Wang, Guoxin Zhang Metal-nitrogen-complexed carbon (MNC) materials have received tremendous attention because of their extraordinary catalytic performance and widely spread applications in the fields of electrocatalysis especially oxygen reduction reaction (ORR). Yet currently, an efficient method for the mass production of MNC electrocatalysts under low costs is still lacking. Herein, we explored a facile low-cost route to construct Co-N-decorated carbon (Co-N-C) materials that were capable of providing a considerably higher ORR performance than commercial 20 wt% Pt/C catalyst (comparable activity, higher long-term cycling stability, and tolerance to methanol contamination). The Co-N-C electrocatalysts were mainly facilitated via the efficient dehalogenation of polyvinyl dichloride or polyvinyl chloride and in situ doping with nitrogen and cobalt ions under mild conditions. Besides the rendered promising electrocatalysts for ORR, our developed method may be capable of converting the halogenated polymeric plastic wastes that are massively accumulated in our environment into value-added carbon-based catalytic materials.Graphical abstractImage
       
  • Electrospun nitrogen-doped carbon nanofibers with tuned microstructure and
           enhanced lithium storage properties
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Chang Liu, Nan Xiao, Yuwei Wang, Ying Zhou, Gang Wang, Hongqiang Li, Yongqiang Ji, Jieshan Qiu Nitrogen-doped carbon materials hold great potential for high-performance lithium storage. However, the excess defects introduced by dominated nitrogen doping methods may lead to a thickened solid electrolyte interphase (SEI), resulting in a higher Li+ diffusion resistance and inferior rate performance. Herein, composite carbon nanofibers (CNFs) with tuned microstructure and relatively high nitrogen content were fabricated by co-electrospinning the mixture of nitrogen-rich pitch, a soft carbon precursor, with polyacrylonitrile (PAN) in controlled mass ratio. The result shows that the SEI formed on the composite CNFs with less surface defects is much thinner yet tighter than that formed on the PAN-based CNFs. As such, the composite CNFs present a double capacity retention of 37.3% to that of the PAN-based CNFs at 10 A g−1. More importantly, the cycle retention of the composite CNFs anode is 88.0% after 1000 cycles at 2 A g−1, much higher than that of PAN-based CNFs (61.5%). It is believed that the improved rate and cycle performance are due to the superior structure and chemical composition of the SEI, which can be attributed to the modified microstructure by addition of nitrogen-rich pitch to a great extent.Graphical abstractHighly stable SEI formed on the low defective carbon surface of NRPP1 significantly enhances lithium storage properties.Image 1
       
  • Gate-enhanced exciton-phonon coupling in photocurrent of (6,5)
           single-walled carbon nanotube based visible sensing field effect
           transistor
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Ki Hong Park, Seung-Hoon Lee, Fumiyuki Toshimitsu, Jihoon Lee, Sung Heum Park, Fujigaya Tsuyohiko, Jae-Won Jang A visible sensing field effect transistor (FET) with a channel length of 100 nm for individual (6,5) single-walled carbon nanotubes (SWCNTs) is fabricated via a selective sorting method using 9,9-dioctyfluorenyl-2,7-diyl–bipyridine (PFO–BPy) polymer. The FET of the (6,5) SWCNTs shows p-type behavior with hundreds of on-off ratios and on-state conductivity of 50 ± 4.0 (Ω m)−1. In addition, the photocurrent of the FET of the (6,5) SWCNTs in the visible range increases (maximum 200 times at 620 nm) with higher gate voltage. E22 transition and PFO-BPy transition are observed in the FET of the (6,5) SWCNTs without application of a gate voltage. Interestingly, exciton-phonon coupled E22 transition due to gate-doping (p-type), which has been reported in photoluminescence and absorption studies, is expected to occur in the photocurrent of the FET at negatively higher gate voltage (≤−4 V). In addition, the exciton-phonon coupled E22 transition is prominently observable when carrier concentration by gate doping becomes approximately two-hundred sixty times (260 ± 43) larger than carrier concentration without application of a gate voltage. This demonstration would be useful for the development of SWCNT-based visible sensors with gate control in the SWCNT devices.
       
  • Pinhole evolution of few-layer graphene during electron tunneling and
           electron transport
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Shuai Tang, Yu Zhang, Ningsheng Xu, Peng Zhao, Runze Zhan, Juncong She, Jun Chen, Shaozhi Deng With graphene as a well-known representative, two-dimensional (2D) atomic crystals are single-layer or few-layer crystalline materials. It is significant to investigate the structure evolution of the 2D atomic crystals in electronic movement process, because it relates to the stability of material properties and the feasibility of the device application. Here, the pinhole evolution of few-layer graphene during electron tunneling and electron transport was observed using in situ transmission electron microscopy (TEM). For few-layer graphene with defects, pinholes expanded with an increase on the electron tunneling current and time, respectively. However, during electron transport processes, with increasing current and time, both, expansion and shrinkage behaviors could be observed among the pinholes distributed within the graphene nanosheet. These behaviors are the result of competition between sublimation and self-repair. Both types of pinhole evolution aim to form a smooth surface with lower surface free energy. The critical boundary conditions for the sublimation and self-repair are determined by the temperature, graphene pinhole structure and active graphene fragment. These findings provide significant reference for the stability of graphene structure and the reliability of graphene based electronic device.Graphical abstractImage 1
       
  • Aligned-SWCNT film laminated nanocomposites: Role of the film on
           mechanical and electrical properties
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Chao Sui, Zixuan Pan, Robert J. Headrick, Yingchao Yang, Chao Wang, Jiangtan Yuan, Xiaodong He, Matteo Pasquali, Jun Lou In this study, well-aligned single-walled carbon nanotube (SWCNT) films were utilized as lamellae to prepare a multifunctional nanocomposite by a feasible ‘layer-by-layer’ preparation method. This structural design can not only dramatically reduce the agglomeration effect of SWCNTs, but also achieve high in-plane stiffness. It was found that the well-aligned SWCNT films contribute to the high stress-transfer between CNTs and present good wettability with epoxy matrix, thereby improving the mechanical enhancement. Interestingly, this laminated structure possesses distinct electrical behaviors under different loading conditions. The electrical resistance linearly increases with the increase of in-plane tensile strain but is insensitive to bending. This work could provide in-depth understanding on the mechanical and electrical properties of CNT-based laminated nanocomposites.Graphical abstractImage 1
       
  • Tuning micro-wrinkled graphene films for stretchable conductors of
           controllable electrical conductivity
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Chunfang Feng, Zhifeng Yi, Ludovic F. Dumée, Fenghua She, Zheng Peng, Weimin Gao, Lingxue Kong Accurately controlling the electrical conductivity of wrinkled graphene or graphene oxide (GO) structures is challenging due to the complex sheet-to-sheet interactions and hierarchical interactions at the nanoscale. In this paper, wrinkled GO films with predictable electrical conductivity by precisely controlling thickness ranging from 0.69 to 1.68 μm were fabricated with a thermal process where a GO-coated polystyrene shrink film was isotropically shrunk. Theoretical and experimental results show consistent dependence of the wrinkle wavelength on the GO film thickness. Beyond a certain thickness threshold, poorly wrinkled structures were formed as GO sheets started delaminating from the shrink films. A coarse-grain molecule model based on molecular dynamic simulation principles was developed to understand the formation of the wrinkles, and establish a relationship between GO thickness and the wrinkle wavelength generated. The electrical resistance was found to decrease when the thickness of the GO films increases. The formed composite film can maintain a stable electrical conductivity after experiencing up to 1000 stretching-release cycles under 10% strain. With controllable electrical conductivity, the reported composites can offer potential applications as a strain sensor with tuneable sensing range and high durability.Graphical abstractImage 1
       
  • Graphene-reinforced silicon oxycarbide composites prepared by phase
           transfer
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Min Yu, Olivier T. Picot, Theo G. Saunders, Ivo Dlouhý, Jinyu Feng, Maria-Magdalena Titirici, Amit Mahajan, Michael J. Reece In order to compensate for cracking, brittleness and low electrical conductivity of polymer-derived silicon oxycarbide (SiOC), graphene was successfully introduced into a SiOC matrix by phase transfer of graphene oxide (GO) from an aqueous (GO dispersed in water) to organic phase (copolymer as SiOC precursor in diethyl ether). Spark plasma sintering (SPS) was used to fully densify composites to ∼2.3g/cm3. The prepared materials were comprehensively characterized and exhibited significant enhancement in the mechanical properties, electrical conductivity and electrochemical performance. Self-assembled lamellar structure of graphene in the SiOC-matrix was achieved, leading to anisotropy in the properties of the composites. The fracture toughness of the SiOC-2vol%GO composite was increased by ∼91%, at the expense of a slight decrease in the flexural strength, compared to the SiOC-matrix. Moreover, the composites exhibited three orders higher electrical conductivity than the SiOC-matrix. The electrical conductivity in the perpendicular direction (σ┴ = 3 × 10−1S/cm) of SiOC-2vol%GO composites was two orders of magnitude higher than that in the parallel direction (σ‖ = 4.7 × 10−3S/cm), owing to the self-assembled lamellar graphene in the SiOC-matrix. The SiOC-2vol%GO composites further showed better electrochemical performance of oxygen reduction reaction (ORR) than pure graphene, exhibiting an onset potential (∼0.75 V vs RHE) and more positive half-wave potential (∼0.6 V vs RHE).Graphical abstractImage 1
       
  • Multi-walled carbon nanotube-coated spiral coils for loss reduction in
           wireless power transfer systems
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Kamran Keramatnejad, Da Wei Li, Hossein Rabiee Golgir, Loic Constantin, Xi Huang, Qi Ming Zou, Jean-Francois Silvain, Stephen Ducharme, Yong Feng Lu Realization of high efficiency and long transmission range in high-frequency wireless power transfer (WPT) systems has always been hindered by the increased resistance due to the eddy current loss occurring in the inductive coils. In this study, multi-walled carbon nanotube-coated copper (MWCNT-Cu) coils are successfully introduced to address this limitation by implementing the frequency-inert MWCNT channels along with using their high-surface areas to realize the electromagnetic shielding of the Cu substrate through multiple reflection mechanisms. At a frequency of 15 MHz, the resistance of the individual MWCNT-Cu coil was reduced to less than 40% of its original value for primitive Cu, leading to more than a four-fold increase in their quality factor. When MWCNT-Cu coils were used as the transmitting component, the transmission efficiency of the WPT system increased from 10.57% to 95.81% at a transmission distance of 4 cm and a frequency of 3.45 MHz. Finally, it was demonstrated that the loss reduction improved as the eddy current loss became more severe in coils with higher inductance values, which makes this approach promising for significantly improving the performance of inductive components in WPT applications.Graphical abstractImage
       
  • Cobalt encapsulated in the nitrogen and sulfur co-doped carbon nanotube
           supported platinum for the oxygen reduction reaction catalyst
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Tae-Hyun Kim, Chi-Young Jung, Ranjith Bose, Sung-Chul Yi In this paper, cobalt encapsulated in nitrogen and sulfur co-doped carbon nanotube (Co-NST) was synthesized through a simple pyrolysis method to impregnate platinum (Pt) nanoparticles. The Co-NST presented a bamboo-like morphology with the high degree of graphitization. Owing to the dual heteroatoms co-doped in the carbon matrix, the Pt supported on the Co-NST (Pt/Co-NST) showed the well-dispersed morphology of the Pt nanoparticles. In addition, the synergistic effect between the Co-NST support and the Pt nanoparticle was observed from the physicochemical characterizations. As a result, the Pt/Co-NST presented improved oxygen reduction reaction (ORR) activity and stability compared to the commercial Pt/C. The mass activity and specific activity of the Pt/Co-NST presented 508.48 mA mgPt−1 and 723.93 μA cmPt−2, respectively, which exhibited more than 3 times higher compared to those of the commercial Pt/C. After repeating 5000 potential cycles, the Pt/Co-NST showed improved stability with 29 mV loss in half-wave potential, while the half-wave potential of the commercial Pt/C was severely decreased by 118 mV.Graphical abstractImage 1
       
  • Ultrathin-graphite foam with high mechanical resilience and
           electroconductibility fabricated through morphology-controlled solid-state
           pyrolysis of polyaniline foam
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Hua Xiao, Pu Xie, Shou Ji Qiu, Min Zhi Rong, Ming Qiu Zhang Three-dimensional carbon-based foam (3D-CF) possesses many fascinating properties such as giant conductivity, high thermal insulation, outstanding mechanical performance, and excellent chemical and thermal stabilities. However, most 3D-CFs acquired by the previously reported fabrication methods have some limitations, such as uncontrollable morphology, plenty of inherent defects, difficult to realize self-standing after removing sacrificial template, and overlapping joint flaws among graphene layers. Although significant research efforts have been devoted to develop 3D foam, it is still a challenging task to obtain 3D-CF with both high conductivity and outstanding mechanical performance, simultaneously. To address this issue, a novel and easy fabricating approach for 3D ultrathin-graphite carbon foam (3D-UGF) was explored by a morphology-retaining pyrolysis of polyaniline foam precursors. The typical 3D-UGF graphitized at 2800 °C exhibited stronger compressive strength and electrical conductivity under the compressive strain of 90%, and remained constant even after 2000 cycles, which are comparable to the previously reported state-of-the-art 3D-CF foam with the same density. Cycling performance of the lithium-sulfur and lithium-air batteries with the 3D-UGF as binder-free cathode is as high as 1590 mAh g−1 and 920 mAh g−1 after deep discharge/charge 100 cycles, respectively.Graphical abstractImage 1
       
  • Multilayered graphene grafted copper wires
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Lee-Woon Jang, Luman Zhang, Mariela Menghini, Hyunjin Cho, Jun Yeon Hwang, Dong Ick Son, Jean-Pierre Locquet, Jin Won Seo Multilayered graphene is grown on copper (Cu) wires by chemical vapor deposition. Mechanical, chemical, thermal and electrical performances are investigated as a function of growth conditions. The graphene layer which makes a volume of approximately 0.02% of the Cu wire enables a 28–37% improvement on tensile strength and strain-to-failure. The chemical resistance of graphene grafted Cu wires increases by 1.5–3 times in nitric acid, aqua regia, and 1M ammonium persulfate etchants. The electrical resistivity of graphene grafted Cu wires remains almost constant with increasing temperature up to 175 °C, while the resistivity degradation of Cu wires without graphene starts to increase from 70 °C. We demonstrate that graphene can protect the Cu wire from thermal oxidation and chemical etchants and can effectively enhance the mechanical and electrical properties of the Cu wire.Graphical abstractImage 1
       
  • Antimicrobial graphene nanoplatelets coatings for silicone catheters
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Rita N. Gomes, Inês Borges, Andreia T. Pereira, André F. Maia, Manuel Pestana, Fernão D. Magalhães, Artur M. Pinto, Inês C. Gonçalves Silicone rubber (SR) peritoneal dialysis (PD) catheters are prone to bacterial adhesion and biofilm formation, which contributes to development of infection and associated morbidity in PD patients. We herein evaluate whether surface immobilization of graphene nanoplatelets (GNP) provides antimicrobial properties to SR. Dip and spray coating were used to deposit a dispersion containing SR and GNP-M5 or its oxidized form (GNP-M5ox) on the surface of silicone. The antimicrobial effect of GNP exposure and oxidation towards Staphylococcus epidermidis was assessed. GNP was successfully exposed on the surface, and while dipping provided better adhesion of either GNP, spraying resulted in uniform and higher surface coverage. Spraying led to enhanced bacterial adhesion comparing to dip coated and uncoated SR, which are similar. However, independently of the technique, GNP-M5ox coatings induced higher bacterial death. As such, SR/GNP-M5ox coating performed by dipping revealed to be the most promising approach, preserving bacterial adhesion levels of silicone while increasing bacterial death to around 80%.For the first time, graphene-based materials antimicrobial activity was evaluated by quantification of bacterial adhesion and viability. The high antibacterial effect, associated with a stable and cytocompatible coating which does not delaminate from SR surface, demonstrates its potential use in silicone biomedical industry.Graphical abstractImage 1
       
  • High salt capacity and high removal rate capacitive deionization enabled
           by hierarchical porous carbons
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Turki N. Baroud, Emmanuel P. Giannelis Capacitive deionization, CDI, has emerged as an attractive alternative for water desalination. Electrodes based on Hierarchically porous carbons, HPCs, consistently show promising electrosorption performance. However, the typically low mesopore fraction and broad pore size distribution limit their utilization in practical applications. Here we report the CDI performance of a series of HPCs synthesized via ice templation possessing a high fraction of mesopore volume (85–93% of total porosity) and tight control over the amount and the size of mesopores (∼6 nm). Electrochemical measurements indicate high rate capability (82% salt retention) and outstanding cycling stability performance (100% capacitance retention over 600 cycles at 0.76 A g−1). In the CDI experiments, the HPCs display high salt capacity (up to ∼ 13 mg g−1) and consistently outperform other high surface areas commercial carbons. The existence of high fraction of mesoporosities enables better utilization of the accessible surfaces of HPCs where the introduction of micropores leads to more than 80% increase in the salt capacity. The HPCs reported here can serve as model electrode systems in studies to delineate the impact of mesoporosity (pore size and volume) on CDI performance and they may pave the way for practical CDI applications.Graphical abstractImage 1
       
  • Flexible binderless capacitors based on P- and N-containing fibrous
           activated carbons from denim cloth waste
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Tomás Cordero-Lanzac, Francisco J. García-Mateos, Juana M. Rosas, José Rodríguez-Mirasol, Tomás Cordero Activated carbon cloths have been prepared from denim cloth waste (DCW) through chemical activation with H3PO4. The effect of the H3PO4/DCW impregnation ratio and the carbonization temperature on the porous texture, the chemical composition, the fibers morphology and the electrochemical performance has been studied. Low H3PO4/DCW impregnation ratios lead to flexible and microporous activated carbon cloths, whereas more fragile and rigid activated carbon cloths with higher external surface area are produced upon increasing the amount of H3PO4. An increase in the carbonization temperature allows for obtaining a more ordered and conductive carbon structure. The activated carbon prepared at 900 °C with an impregnation ratio of 0.5 (wt. H3PO4/wt. DCW) exhibits the best performance as electric double layer capacitor. This electrode shows a specific surface area of 2032 m2 g−1 and the highest registered gravimetric capacitance (237 F g−1). Moreover, its flexibility minimizes the contact resistance in the electrode, thus increasing the feasibility of working at higher current densities than the other synthesized electrodes.Graphical abstractImage
       
  • Flexible pressure sensors using highly-oriented and free-standing carbon
           nanotube sheets
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Sungwoo Chun, Wonkyeong Son, Changsoon Choi Carbon allotropes are strong candidates for pressure sensing materials in flexible electronics due to their extraordinary mechanical and electrical properties. However, the complexity of the conventional transfer process for these allotropes, the success of which is strongly dependent on the surface conditions of the substrates, limits their feasibility for use as pressure sensors. Thus, we propose a method to create flexible pressure sensors using highly-oriented and free-standing hydrophobic carbon nanotube (CNT) sheets. When drawn from a sidewall of a carbon nanotube forest, these sheets only require a single transfer process without any chemical treatment, thereby facilitating a simple, cost-effective transfer method. The resulting sensors exhibit high sensitivity and fast response characteristics for both statically and dynamically applied pressures. In addition, the highly-oriented structure of these CNT sheets results in distinctive response characteristics for bi-axially applied bending strains. It was also confirmed that the sheets can be easily transferred onto any substrate, including those with rough surfaces, due to the naturally formed free-standing structure. In this work, we present the intact transfer of a CNT sheet onto a micro-patterned substrate representing a rough surface and demonstrate the accompanying typical piezoresistive responses of the resulting pressure sensor.Graphical abstractImage 1
       
  • Raman resonance profile of an individual confined long linear carbon chain
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Sebastian Heeg, Lei Shi, Thomas Pichler, Lukas Novotny This paper reports tip-enhanced, polarization dependent and excitation energy dependent Raman measurements of an individual long linear carbon chain confined in a double-walled carbon nanotube. We determine the band gap of the chain (2.093 eV) from a Raman resonance profile with a line width Γ=145meV, which corresponds to a lifetime of τ=4.5fs for the excited state of the chain. In the absence of external perturbations, this suggests that the chain's excited state dynamics depend on the confinement inside the nanotube and therefore on the chirality of the encasing carbon nanotube.Graphical abstractImage 1
       
  • An effective in situ reduction strategy assisted by supercritical fluids
           for the preparation of graphene - polymer composites
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Suchithra Padmajan Sasikala, Wilfrid Neri, Philippe Poulin, Cyril Aymonier The chemical/thermal in situ reduction of graphene oxide (GO) in GO-polymer composite is consistently challenged by the presence of undesirable chemical residues/temperature degradation restriction of the polymer. In order to tackle this problem, an effective in situ supercritical fluid reduction strategy comprising of supercritical CO2 and ethanol binary system under N2 atmosphere was developed by stepwise comparison of different reduction methods for graphene oxide-polyvinyl alcohol (GO-PVA) composite films. The resulting rGO-PVA composite films comprising of 10 wt% rGO showed an electrical conductivity of 51.7 S/m-and Young's modulus of 3.1 GPa. Different weight loadings of GO in the polymer composite films were found to affect the electrical and mechanical properties of the resulting rGO-polymer films. The in situ supercritical fluid reduction strategy was demonstrated further for successfully obtaining rGO-polyethylene glycol films (rGO-PEG) and rGO-PVA fiber.Graphical abstractSupercritical fluids mediated in situ reduction as a new paradigm in preparation of reduced graphene oxide-polymer composites.Image 1
       
  • Tuning surface chemistry and morphology of graphene oxide by γ-ray
           irradiation for improved performance of perovskite photovoltaics
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Jae Sang Cho, Woongsik Jang, Sung Cik Mun, Minji Yi, Jong Hyeok Park, Dong Hwan Wang We demonstrated a simple and effective modification of graphene oxide (GO) to enhance the device performance of perovskite photovoltaics. The surface chemistry and morphology of GO was tailored by irradiating aqueous GO solution with 60Co γ-ray. During the irradiation, hydroxyl radicals were believed to be released from water radiolysis and oxidized the surface of pristine GO sheets, supposedly. Furthermore, large GO agglomerates scattered as individual GO sheets with small lateral dimensions, which is advantageous to uniform distribution of GO sheets in PEDOT:PSS layer. PEDOT:PSS layer with γ-ray irradiated GO (γ-GO) facilitated efficient hole transport properties in perovskite solar cells. PEDOT:PSS layer became more hydrophobic by embedding γ-GO after thermal annealing and thus improved the crystallinity of perovskite layer on top of the PEDOT:PSS. Consequently, embedding γ-GO in PEDOT:PSS layer resulted in better electrical properties than PEDOT:PSS layer without GO or with pristine GO. As a result, power conversion efficiency was improved owing to increased charge generation/extraction, and photoluminescence in the perovskite photoactive layer.Graphical abstractImage 1
       
  • Formation of hollow carbon nanoshells from thiol stabilised silver
           nanoparticles via heat treatment
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Julie A. Watts, Mike W. Fay, Graham A. Rance, Paul D. Brown, Andrei N. Khlobystov Uniform, < 10 nm sized, hollow carbon nano-shells (HCNS) have been prepared via a single-step, thermal treatment of alkanethiol stabilised Ag nanoparticles (TS-AgNP). Direct evidence for the formation of spherical HCNS from TS-AgNP is provided by in situ MEMS heating on Si3N4 supports within a TEM, and ex situ thermal processing of TS-AgNP on carbon nanotube supports. A mechanism is proposed for the thermally driven, templated formation of HCNS from the TS-AgNP stabilising layer, with Ag catalysing the graphitisation of carbon in advance of thermally induced AgNP template removal. This facile processing route provides for excellent size control of the HCNS product via appropriate AgNP template selection. However, a rapid rate of heating was found to be crucial for the formation of well-defined HCNS, whilst a slow heating rate gave a much more disrupted product, comprising predominantly lacy carbon with decreased levels of graphitic ordering, reflecting a competition between the thermal transformation of the TS-layer and the rate of removal of the AgNP template.Graphical abstractBright field, diffraction contrast TEM micrographs of (a) TS-AgNP/Si3N4 before rapid in situ heating to 850 °C (TP-1); and (b) the resultant HCNS, imaged at 850 °C.Image 1
       
  • Graphitization of diamond by laser-accelerated proton beams
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): M. Barberio, S. Vallières, M. Scisciò, G. Kolhatkar, A. Ruediger, P. Antici In this work, we investigate the interaction between fast energetic proton beams generated by laser-plasma based accelerators with carbon lattices of graphite and diamond. Theoretical and experimental results indicate that these proton beams cause both, a low sputtering of carbon atoms from lattices (estimated to be in the order of 3 × 10−8 displacements per atom for each single shot), and a heating (inside the target and within a depth of about 10 μm below the surface) at a temperature close to the sp3/sp2 transition. The defects generated inside the lattices by the atom displacements cause the random formation of amorphous carbon islands, while the higher temperature causes the start of diamond partial graphitization. All the results suggest the impossibility to use diamond as detector in laser-driven accelerators when placed close to the source, while they confirm that proton beams can be used as alternative to classical laser or ion beam methods to graphitize diamond in specific optoelectronic applications.Graphical abstractImage 1
       
  • Charge-transfer mediated nanopore-controlled pyrene derivatives/graphene
           colloids
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Austina D. Putri, Nurul Chotimah, Sanjeev Kumar Ujjain, Shuwen Wang, Ryusuke Futamura, Fernando Vallejos-Burgos, Fitri Khoerunnisa, Masafumi Morimoto, Zhipeng Wang, Yoshiyuki Hattori, Toshio Sakai, Katsumi Kaneko Electrically-conductive graphene colloids with tuned nanoporosity are promising materials for numerous applications. As charge-transfer interaction enhances electrical conductivity of polyaromatic hydrocarbon crystals, we intercalated water-soluble pyrene derivatives such as pyrene-boronic acid in nanoporous graphene by reduction of a mixture of graphene oxides and pyrene derivatives. The pyrene derivative intercalation increases more than twice both microporosity and mesoporosity. The N2 adsorption isotherms at 77 K of all samples have low-pressure adsorption hysteresis due to inaccessible small microporosity; the total porosity evaluated by water adsorption at 298 K is almost twice that of N2 adsorption. These adsorption measurements together with X-ray diffraction suggest the presence of a pore mouth structure whose width is about 0.4 nm. The charge-transfer interaction between the pyrene derivative and porous graphene is evidenced by a high frequency shift of the G band of Raman spectrum, appearance of a new optical absorption band, and the increase in electrical conductivity. The intercalation of pyrene-boronic acid through charge-transfer interaction increases the voltammetric charge of cyclic voltammogram for nanoporous graphene owing to an enhanced ion-accessibility from 3% to 54%, which indicates their high application potential for electrochemical studies.Graphical abstractImage 1
       
  • Efficient defect healing and ultralow sheet resistance of laser-assisted
           reduced graphene oxide at ambient conditions
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Aspasia Antonelou, Labrini Sygellou, Katerina Vrettos, Vasilios Georgakilas, Spyros N. Yannopoulos Reduction of graphene oxide (GO) to a low-resistance product is one of the most versatile routes to obtain large volume graphene-based materials. A number of chemical and thermal methods are being applied to achieve this goal, albeit each one is bound to certain disadvantages and limitations. Laser-assisted reduction has emerged as a promising method apt to overcome issues related to chemical and thermal reduction. Despite that a large number of efforts have been focused on laser-induced reduction of GO, its transformation to high quality reduced GO still remains a bottleneck. Here, it is shown that low-cost, millisecond lasers, widely used in the welding industry, achieve excellent reduction of GO to a product with the lowest sheet resistance yet reported by any laser-assisted method. For comparison, GO is reduced by chemical and thermal methods. Raman and x-ray photoelectron spectroscopies are applied to investigate the underlying structural changes providing evidence for the removal of oxygen-containing species and defect healing. Operation at ambient conditions, single pulse irradiation and a 2.60 mm wide focusing spot, demonstrate the high potential of this approach to the scalability of the reduction process towards producing large volumes of high-quality reduced graphene oxide at low cost.Graphical abstractImage 1
       
  • Structural determination of single-walled carbon nanotube with an
           intramolecular junction and its electrical transport property
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Taekyung Kim, Jian-Min Zuo By utilizing a novel design of an electronic device with microfabricated through-etched slits for transmission electron microscopy (TEM), single-walled carbon nanotubes (SWNTs) suspended over two metal electrodes were successfully characterized. A semiconducting-semiconducting intramolecular junction (IMJ) was found from a change in chirality along the tube. Interestingly non-linear current-voltage characteristic was found despite almost negligible difference in the band-gap energy (13 meV). The non-linear electrical transport property can be caused by asymmetric defect states positioned in the band-gap of two semiconducting tubes, which make one as donor (similar to a p-type semiconductor) and the other as acceptor (similar to n-type semiconductor). The strain by deformation along the tube can also cause the electrical non-linearity.Graphical abstractImage 1
       
  • Enhanced mechanical properties of aluminum based composites reinforced by
           chemically oxidized carbon nanotubes
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Baisong Guo, Xinming Zhang, Xi Cen, Biao Chen, Xinhua Wang, Min Song, Song Ni, Jianhong Yi, Tao Shen, Yong Du Uniform dispersion and suitable interface are two critical issues to realize the high strengthening potential of carbon nanotubes (CNTs) in metal based composites. In this work, surface modification of CNTs was applied to simultaneously overcome these two challenges in Al matrix composites by a chemical oxidization method. It was found that the functional groups, such as hydroxyl and carboxyl groups, can be successfully decorated on the surface of CNTs by chemical oxidization, thus improving the dispersion of CNTs in ethanol. Concurrently, the morphology of oxidized CNTs and the Al-CNTs interface depend strongly on the activity of the applied oxidants. The mixture of sulphuric acid and hydrogen peroxide can slightly etch the outer walls of CNTs, which benefits the anchoring bonding between the CNTs inner walls and Al matrix, and improves the interface stability, hence exploits the load bearing capacity of the CNTs inner walls and eventually leads to the effective load transfer between Al and CNTs. The outstanding reinforcing effect of surface-modified CNTs was investigated and discussed by the strengthening models. This work provides a new approach to uniformly disperse CNTs and improve interfacial bonding for CNTs reinforced composites simultaneously.Graphical abstractImage
       
  • 19-Fold thermal conductivity increase of carbon nanotube bundles toward
           high-end thermal design applications
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Yangsu Xie, Tianyu Wang, Bowen Zhu, Chaoyi Yan, Peixin Zhang, Xinwei Wang, Gyula Eres In high temperature annealing of carbon nanotube (CNTs) bundles for structure and thermal conductivity (κ) improvement, the statistical errors from sample-wide structure variation and sample transfer/preparation significantly overshadows the understanding of structure-κ correlation and change. In this work, the sequential process of current-induced thermal annealing (CITA) on improving the structure, electrical and thermal conductivities of chemical vapor deposition grown CNT bundles is studied for the first time. Our in-situ κ measurement using the transient electro-thermal technique uncovers the conjugated dynamic electrical, thermal, and structural properties. The electrical resistance and thermal diffusivity evolution of CNT bundles during CITA is studied. The thermal diffusivity and κ before and after CITA are measured from room temperature down to 10 K to uncover the reduction of defect density and enhancement of inter-tube connection strength after CITA. Our micro-Raman spectroscopy study from the most annealed region to the non-annealed region reveals significantly improved order in sp2 bonding carbon structure and reduced defects along the sample length. The resulting κ has 5–19 times increase at the most annealed region of CNT bundles. The intrinsic κ of CNT walls against the annealing temperature is also determined, which reaches a level as high as 754 W/m·K after CITA.Graphical abstractImage 1
       
  • Hybrid spray-coating, laser-scribing and ink-dispensing of graphene
           sensors/arrays with tunable piezoresistivity for in situ monitoring of
           composites
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Sida Luo, Yong Wang, Guantao Wang, Fu Liu, Yujiang Zhai, Yun Luo Graphene based nanotechnology has offered a variety of novel strategies for enabling self-sensing and diagnosing functionalities for next-generation composites. In comparison to traditional methods with complicated procedure and limited scalability, a new process is impending for graphene sensor fabrication with designable shape and controllable performance. Toward this goal, this paper combined multiple computer-aided processes for designing graphene thin film sensors and arrays on composites, including spray-coating, laser-scribing and ink-dispensing. The processing-structure-property relationship was systematically investigated for understanding the piezoresistive performance of the laser scribed graphene (LSG) sensors. It is determined that by increasing the cycle time of laser irradiation, the gauge factor could be tailored up to 3 orders of magnitude from ∼450 to ∼0.6. The accumulated bump-shaped structure originated from intenser reduction of graphene oxide (GO) is believed to disrupt the efficiency of load-transfer and degrade the resulting performance. With the optimized recipe, versatility of LSG sensors and arrays deployed with ink-printed circuits was further explored for monitoring and mapping large-scale deformation and strain distribution of polymeric composites.Graphical abstractImage 1
       
  • Scaling of binding affinities and cooperativities of surfactants on carbon
           nanotubes
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Minsuk Park, Junmo Park, Jiyun Lee, Sang-Yong Ju High-end applications of single-walled carbon nanotube (SWNT) require detailed understanding of their binding affinity (Kd) with surfactants. Here, we quantitatively determined the comprehensive Kd and aggregation number (γ) of nine nonionic and anionic surfactants according to SWNT chirality. Photoluminescence (PL)-based titration using flavin mononucleotide (FMN)-SWNT complexes showing the largest redshifted optical transition enabled quantitative comparison of the surfactants and displayed distinct first and second regimes which correspond to partial and full replacements of FMN, respectively. Especially, the second transition exhibited sigmoidal PL change whose middle point denoted by the inverse of Kd slightly differs from critical micelle concentration of surfactant alone, depending on its functional groups. Moreover, nonionic surfactants displayed larger Kd and lower γ values than the anionic did. Specifically, Kd values between Pluronic F108 and sodium dodecyl sulfonate differ by four orders of magnitude. Such differences were rationalized in terms of the occupied volume of the micelle based on the hydrodynamic volume and γ. During the replacement, Kd and γ were affected by the degree of surfactant rearrangement induced by aging process, leading to more stable complex. Scaling the interactions between surfactant and SWNT provides useful guidelines to design novel SWNT sorting method using more than two surfactants.Graphical abstractImage 1
       
  • Novel timed and self-resistive heating shape memory polymer hybrid for
           large area and energy efficient application
    • Abstract: Publication date: Available online 17 July 2018Source: CarbonAuthor(s): Manuela Loeblein, Asaf Bolker, Zhi Lin Ngoh, Lanxin Li, Eliana Wallach, Siu Hon Tsang, Matthieu Pawlik, Ronen Verker, Nurit Atar, Irina Gouzman, Edwin Hang Tong Teo Shape memory polymers (SMPs) are a polymeric smart material that can register two or more temporary shapes and transform to one another through an external stimulus. Despite their compactness and customizability, SMPs haven't been able to be adopted for mainstream applications. Since the majority of SMPs are triggered by heat, and SMPs have a very poor thermal conductivity, large thermal gradients within the polymer appear which cause slow response, inhomogeneous heat distribution and thus non-uniform transformation of shapes and cracks. Many have attempted to improve their thermal performance through the incorporation of filler-based nanomaterials. However, the outcome is ineffective as the spatial dispersion of fillers within the SMP is inhomogeneous and leads to performance loss. Contrastingly, the herein presented new class of nanocomposite-SMP, composed by 3D-foam fillers, showcase a much more efficient SMP adaptable to larger area with faster transformation speed and without any performance loss. Furthermore, the improved thermal properties lead to a decrease in required input energy, as well as render the SMP a self-heating capability which can be further designed into timed multi-step SMP behavior.Graphical abstractImage 1
       
  • Ultralight graphene micro-popcorns for multifunctional composite
           applications
    • Abstract: Publication date: Available online 17 July 2018Source: CarbonAuthor(s): Chen Chen, Jiabin Xi, Yin Han, Li Peng, Weiwei Gao, Zhen Xu, Chao Gao Graphene has been widely applied in polymer nanocomposites due to its charming physical and chemical properties. However, the performance of graphene/polymer composite is hampered by the strong stacking tendency of graphene sheets. Here we introduce graphene micropopcorns (GMPs) with a hollow structure and a low stacking degree as an efficient additive for multifunctional composites. GMPs are massively fabricated via a facile thermal treatment of spray-dried graphene oxide (GO) powder. GMPs feature a low tap density (6–8 mg cm−3), a high specific surface area (947 m2 g−1) and a good solvent absorption capability (62 g g−1). This micro form of graphene can act as electrical conductive fillers with a low percolation threshold of 0.18 vol% and microcapsules of phase change materials with a 358% enhancement in thermal conductivity. Besides, the microwave absorption (MA) performance of GMPs/paraffin composites outperforms most graphene-based materials ever reported but with a record-low filler content (2.5 wt%). The large-scale producible GMPs enable an efficient method to utilize graphene to grant conventional materials with better performances and new functions.Graphical abstractImage 1
       
  • A simple means of producing highly transparent graphene on sapphire using
           chemical vapor deposition on a copper catalyst
    • Abstract: Publication date: Available online 17 July 2018Source: CarbonAuthor(s): Gloria Anemone, Esteban Climent-Pascual, Amjad Al Taleb, Hak Ki Yu, Felix Jiménez-Villacorta, Carlos Prieto, Alec M. Wodtke, Alicia De Andrés, Daniel Farías Chemical vapor deposition (CVD) is one of the best ways to scalably grow low cost, high quality graphene on metal substrates; unfortunately, it not ideal for producing graphene on dielectric substrates. Here, we demontrate production of a high quality graphene layer on Sapphire using CVD with a copper catalyst. The catalyst consists of a thin copper film grown epitaxially on α-Al2O3 (0001). After CVD growth of Graphene, the copper can be removed by simple evaporation in the presence of a carbon source (C2H4). We characterized the resulting graphene layer using Raman spectroscopy, atomic force microscopy (AFM), optical transmission and helium atom scattering (HAS). The sample exhibited a reduced Raman D peak and an excellent 2D to G ratio. AFM and HAS show large graphene domains over a macroscopic region. We measured >86% transparency over the visible spectrum.Graphical abstractImage 1
       
  • Influence of sonication conditions and wrapping type on yield and
           fluorescent quality of noncovalently functionalized single-walled carbon
           nanotubes
    • Abstract: Publication date: Available online 17 July 2018Source: CarbonAuthor(s): Nathaniel Kallmyer, Trinh Huynh, Joseph Connor Graves, Joseph Musielewicz, Denis Tamiev, Nigel Reuel As nanomaterials have become more accessible, nanoscale biosensor research has expanded to many useful applications. One such nanomaterial is the single-walled carbon nanotube (SWCNT), which fluoresces in the near-infrared biological window, making it ideal for in vivo applications. SWCNT can be suspended in water when non-covalently functionalized with an amphiphilic polymer or surfactant (e.g. ‘wrapped’); the suspended SWCNT can act as a simple optical probe or as a sensor by engineering the wrapping to have selective domains. The process of suspending nanotubes is typically achieved by sonication. While much application-focused research has been performed on SWCNT sensors and probes, little has been done to understand factors affecting SWCNT fluorescent quality after suspension. We explored effects of sonication power and duration on an array of nine potential wrappings including proteins, DNA, oligosaccharides, polysaccharides, synthetic polymers, and surfactant solutions. Optimal sonication conditions were found to vary on an individual wrapping basis. These trends may be used to predict optimal processing conditions to suspend SWCNT with maximal start fluorescence for various wrappings, improving dynamic range and sensitivity. These results also point to the need for control of sonication conditions in large scale synthesis to ensure tighter batch-to-batch reproducibility of nanotube sensors.Graphical abstractImage 1
       
  • Wood-inspired multi-channel tubular graphene network for high-performance
           lithium-sulfur batteries
    • Abstract: Publication date: Available online 17 July 2018Source: CarbonAuthor(s): Changxia Li, Jingyi Yu, Shi-Lei Xue, Zhihua Cheng, Guoqiang Sun, Jing Zhang, Rudan Huang, Liangti Qu Hierarchical porous structure plays a vital role in various energy storage systems. Herein, a wood-inspired multi-channel tubular graphene (MCTG) architecture is fabricated by template-directed chemical vapor deposition (CVD). The multi-channel template is assembled via a facile hydrothermal and freeze-drying method with Si as precursor. The unique multi-channel tubular graphene architecture reveals distinct advantages for lithium-sulfur (Li-S) batteries. The curved tubular interior space with a pore volume of 2.141 cm3 g−1 can accommodate active sulfur and anchor soluble polysulfides, while the 3D multi-channel network favors rapid mass transport and ion diffusion. Furthermore, the CVD grown few-layer graphene offers good electron conductivity, while the enlarged (002) spacing (0.35–0.41 nm) of graphene layers provide more space for sulfur storage and Li+ diffusion. Benefiting from these merits, the MCTG/S cathode (loaded with 70 wt% sulfur) achieves a high initial discharge capacity of 1390 mAh g−1 at 0.1 C rate, excellent rate capability up to 8 C and a slow capacity decay rate of 0.078% per cycle during 500 cycles. This type of MCTG will also play an important role in gas adsorption, solar steam generation, catalysis, and so on.Graphical abstractImage 1
       
  • Multi-channel FeP@C octahedra anchored on reduced graphene oxide nanosheet
           with efficient performance for lithium-ion batteries
    • Abstract: Publication date: Available online 12 July 2018Source: CarbonAuthor(s): Peipei Zhu, Ze Zhang, Shiji Hao, Bowei Zhang, Pengfei Zhao, Ji Yu, Jianxin Cai, Yizhong Huang, Zhenyu Yang Iron phosphide (FeP) is a promising anode material for Li-ion batteries (LIBs) due to its low cost and high theoretical capacity. To design FeP anode materials with multi-channels for both ions and electrons will greatly help to realize fast ion and electron diffusion and high-rate capability of LIBs, and effectively overcome its intrinsic shortcomings of low conductivity and large volume expansion. Herein, a novel octahedral multi-channel FeP@C/rGO composite has been fabricated by a simple solvothermal process followed by carbonization and phosphorization. The as-prepared FeP@C/rGO composite displays an excellent rate capacity (497 mAh g−1 at 5 A g−1), as well as a high reversible capacity (1080 mAh g−1 at 0.1 A g−1) and superior cyclability with a capacity decay rate of 0.04% per cycle upon 500 cycles. The outstanding electrochemical performance of FeP@C/rGO composite can be attributed to the unique stable carbon octahedral multi-channel frameworks and N/P co-doping interconnect graphene conductive network, which significantly facilitate the Li-ion and electron transfer and accommodate the large volume change during cycling. This work shows a feasible strategy to fabricate FeP-based composites with multi-channels structure as a high-performance anode for lithium-ion batteries.Graphical abstractImage 1
       
  • Low percolation threshold in highly conducting graphene
           nanoplatelets/glass composite coatings
    • Abstract: Publication date: Available online 12 July 2018Source: CarbonAuthor(s): A. Nistal, E. Garcia, D. Pérez -Coll, C. Prieto, M. Belmonte, M.I. Osendi, P. Miranzo Thermal sprayed thick glass coatings with a small percentage of multilayer graphene nanoplatelets (GNP) demonstrate electrical functionality with a quite remarkable low percolation limit (1.18 vol.%). This low critical content and the high electrical conductivity (∼40 S m−1) observed for the in-plane direction are related to the peculiar coating microstructure, formed by the pileup of lamellar amorphous particles decorated by GNP mostly following a surface parallel orientation. The general effective media model fitting to the electrical conductivity data for these coatings suggests a 3D connectivity of graphene and estimates an upper limit conductivity for the GNP of 105 S m−1. Hall Effect shows the n-type behavior intrinsic to the SiO2/graphene interface, and carrier density and mobility rising with the GNP content. In addition, the coatings evidence a very high solar absorptivity that jointly with their high electrical conductivity broadens their potential applications, among others, for electromagnetic interference shielding or as photothermal detector and solar absorber for solar steam generation and water desalination.Graphical abstractImage 1
       
  • Improving the thermal stability of carbon nanotubes and their field
           emission characteristics by adding boron and phosphorus compounds
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Octia Floweri, Hyeonjee Jo, Yongho Seo, Naesung Lee Adding boron and phosphorus compounds substantially improved the thermal stability of carbon nanotubes (CNTs), increasing their oxidation temperature by 37–173 °C. Analysis of the B1s and P2p X-ray photoelectron spectral peaks suggested that the boron and phosphorus compounds chemically poisoned active sites of CNTs by forming C–O–B, C–O–P and C–P–O bonds. These interactions drove away oxygen from the active sites and delayed their oxidative reactions. Incorporation of these compounds in CNT pastes followed by high-temperature heat treatment in a vacuum considerably enhanced their field emission characteristics, evaluated by measuring current–voltage (I–V) curves and long-term stability, for an X-ray tube application.Graphical abstractFunctionalization of CNTs with B- and P-compounds protects their surface from oxidation.Image 1
       
  • Thermal conductivity enhancement of reduced graphene oxide via chemical
           defect healing for efficient heat dissipation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Chae Bin Kim, Janggeon Lee, Jaehyun Cho, Munju Goh As next-generation miniaturized electronics are being developed with higher power density, a need for effectively dissipating the generated heat during the device operation is becoming ever greater. Nano carbons such as graphene are strong candidates for heat dissipating materials with lightweights owing to their low densities with extraordinary thermal properties rooted from their highly crystalline and conjugated structures. Starting from a relatively less ordered, cheaper, and mass producible graphene oxide (GO), to this end, we herein describe a sequential chemical transformation to obtain a higher ordered crystalline and conjugated structure of the GO. A conventional reduction followed by a chemical defect healing process via intramolecular cross-dehydrogenative coupling gradually increased graphitic and crystalline structures of the GO as evidenced by a variety of spectroscopic and microscopic experiments. Consequently, the thermal conductivity of the final product was enhanced to 9.90 W/mK, corresponding to over 500% of the starting GO (1.92 W/mK). Moreover, the defect healed GO itself was successfully used as a heat dissipating material, quickly lowering its temperature by ∼36 °C during a continuous heating at 100 °C. Finally, we also demonstrated the defect healed GO as filler to enhance the thermal conductivity of the polymeric composites.Graphical abstractImage 1
       
  • A novel approach to strengthen naturally pored wood for highly efficient
           photodegradation
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Hui Mei, Weizhao Huang, Chengxu Hua, Yawei Xu, Laifei Cheng Carbonaceous materials with unique microstructure obtained by pyrolyzing renewable and environment-friendly nature plants have promising applications in areas such as battery and catalyst support. However, unexpected cracks accompanied by low oxidation resistance retard further development. In this study, a thin SiC coating for strengthening purpose was in-situ deposited on biomorphic porous carbon materials fabricated by pyrolyzing wood while maintaining low density. Continuously ordered microchannel structures from carbonized nature wood with a diameter of ca. 20 μm was completely replicated after depositing SiC coating, resulting in the good anisotropy in mechanical and thermal properties. The thin SiC coating was found to greatly increase compressive strength from 26.4 to 47.4 MPa and thermal conductivity from 0.49 to 14.94 W/m K in the axial direction with improved oxidation resistance of weight loss from 78.5% to 1.51%. In the radial direction, however, the increase of the two properties was lower due to the longitudinal microchannel structure. Feasibility of the biomorphic carbon serving as catalyst support with highly developed continuous channels was evaluated by loading typical molybdenum disulfide (MoS2). Result shows a significant improvement in both adsorption and photodegradation efficiency against the pure MoS2, which is because of the enlarged specific surface area of the catalyst.Graphical abstractImage
       
  • Pt nanocrystals grown on three-dimensional architectures made from
           graphene and MoS2 nanosheets: Highly efficient multifunctional
           electrocatalysts toward hydrogen evolution and methanol oxidation
           reactions
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Zhiqiang Gao, Miaomiao Li, Jiayu Wang, Jixin Zhu, Xianmin Zhao, Huajie Huang, Jianfeng Zhang, Yuping Wu, Yongsheng Fu, Xin Wang Although electrocatalytic hydrogen evolution and methanol oxidation have long been regarded as promising technologies for future energy production and conversion, the incapability of the electrode catalysts poses a major impediment to their large-scale commercialization. Herein, we present a facile co-assembly approach to the fabrication of Pt nanocrystals grown on 3D architectures built from ultrathin graphene and MoS2 nanosheets. By virtue of their unique textural features, such as large specific surface area, 3D cross-linked porous framework, homogeneous distribution of Pt nanoparticles, and excellent electron conductivity, the resulting Pt/graphene-MoS2 architectures possess multifunctional catalytic activities toward hydrogen evolution and methanol oxidation reactions, accompanied by high durability and strong poison tolerance, which significantly outperform those for conventional Pt/carbon black, Pt/graphene, and Pt/MoS2 catalysts. It is believed that such a simple bottom-up design concept can open up new possibilities for the up-scale synthesis of various 3D hybrid architectures with metals or metal oxides for energy-related applications.Graphical abstractA facile and cost-effective co-assembly approach is developed to synthesize Pt nanocrystals grown on 3D architectures built from ultrathin graphene and exfoliated MoS2 nanosheets. Owing to their attractive structural features, the resulting hybrids exhibit multifunctional electrocatalytic ability toward hydrogen evolution and methanol oxidation reactions.Image 1
       
  • Tailoring of polycrystalline diamond surfaces from hydrophilic to
           superhydrophobic via synergistic chemical plus micro-structuring processes
           
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): A. Gabriela Montaño-Figueroa, Jesus J. Alcantar-Peña, Pablo Tirado, Alejandro Abraham, Elida de Obaldia, Orlando Auciello The wettability properties of the surfaces of polycrystalline diamond films, grown by Hot Filament Chemical Vapor Deposition, with different grain sizes, ranging from microcrystalline diamond (MCD), to nanocrystalline diamond (NCD), to ultrananocrystalline diamond (UNCD), were successfully tailored from as-grown flat semi-hydrophobic to hydrophilic surfaces, via oxygen (O2) plasma treatment, to highly-hydrophobic by carbon tetrafluoride (CF4) plasma treatment, and to super-hydrophobic diamond surface, via synergistic tailoring of surface chemistry and 3-D texturing. Raman spectroscopy analysis and secondary electron microscopy revealed the Hydrogen-surface termination and increased grain size, respectively, of the diamond films. Atomic Force Microscopy imaging of the plasma-treated UNCD films revealed no significant change in the surface roughness after either O2 or CF4 treatments. Nevertheless, a surface-chemistry alteration was confirmed by X-ray Photoelectron Spectroscopy. Finally, the synergistic combination of 3-D surface structuring and plasma-induced fluorine atoms surface termination of UNCD films produced a superhydrophobic state as revealed by a Water Contact Angle (WCA) close to ∼174°, thus producing the highest superhydrophobic surface of diamond material demonstrated today. The metastable Cassie-Baxter state, for the superhydrophobic 3-D UNCD surface, was demonstrated via a close correlation between the mathematical calculation based on the Cassie-Baxter Model and the experimental measurement of the WCA.Graphical abstractImage
       
  • Buckypaper embedded self-sensing composite for real-time fatigue damage
           diagnosis and prognosis
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Siddhant Datta, Rajesh Kumar Neerukatti, Aditi Chattopadhyay In this study, buckypaper (BP) membranes have been used to introduce self-sensing capability in glass fiber reinforced polymer matrix (GFRP) laminates by embedding them in the interlaminar region of the laminates. Piezoresistive characterization studies were conducted by subjecting the self-sensing GFRP (SGFRP) specimens to cyclic loading and high sensitivity to strain was observed. A measurement model for real-time quantification of fatigue crack, developed using in-situ resistance measurements obtained under fatigue loading, was used to quantify fatigue crack length in real time. The fatigue crack growth rates and the nature of crack propagation in baseline and SGFRP specimens were compared. The results show that the introduction of BP reduced the average crack growth rate by an order of magnitude as a result of crack tip blunting during fatigue, while facilitating real time strain sensing and damage quantification. A fully probabilistic prognosis methodology was also developed by combining the in-situ measurement model with a machine learning based prognosis model to accurately predict the real-time fatigue crack propagation using sequential Bayesian techniques.Graphical abstractImage
       
  • Comparative nanostructure analysis of gasoline turbocharged direct
           injection and diesel soot-in-oil with carbon black
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): S.A. Pfau, A. La Rocca, E. Haffner-Staton, G.A. Rance, M.W. Fay, R.J. Brough, S. Malizia Two gasoline turbocharged direct injection (GTDI) and two diesel soot-in-oil samples were compared with one flame-generated soot sample. High resolution transmission electron microscopy imaging was employed for the initial qualitative assessment of the soot morphology. Carbon black and diesel soot both exhibit core-shell structures, comprising an amorphous core surrounded by graphene layers; only diesel soot has particles with multiple cores. In addition to such particles, GTDI soot also exhibits entirely amorphous structures, of which some contain crystalline particles only a few nanometers in diameter. Subsequent quantification of the nanostructure by fringe analysis indicates differences between the samples in terms of length, tortuosity, and separation of the graphitic fringes. The shortest fringes are exhibited by the GTDI samples, whilst the diesel soot and carbon black fringes are 9.7% and 15.1% longer, respectively. Fringe tortuosity is similar across the internal combustion engine samples, but lower for the carbon black sample. In contrast, fringe separation varies continuously among the samples. Raman spectroscopy further confirms the observed differences. The GTDI soot samples contain the highest fraction of amorphous carbon and defective graphitic structures, followed by diesel soot and carbon black respectively. The AD1:AG ratios correlate linearly with both the fringe length and fringe separation.Graphical abstractImage
       
  • Size- and temperature-dependent bending rigidity of graphene using modal
           analysis
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Banafsheh Sajadi, Simon van Hemert, Behrouz Arash, Pierpaolo Belardinelli, Peter G. Steeneken, Farbod Alijani The bending rigidity of two-dimensional (2D) materials is a key parameter for understanding the mechanics of 2D NEMS devices. The apparent bending rigidity of graphene membranes at macroscopic scale differs from theoretical predictions at micro-scale. This difference is believed to originate from thermally induced dynamic ripples in these atomically thin membranes. In this paper, we perform modal analysis to estimate the effective bending rigidity of graphene membranes from the frequency spectrum of their Brownian motion. Our method is based on fitting the resonance frequencies obtained from the Brownian motion in molecular dynamics simulations, to those obtained from a continuum mechanics model, with bending rigidity and pretension as the fit parameters. In this way, the effective bending rigidity of the membrane and its temperature and size dependence, are extracted, while including the effects of dynamic ripples and thermal fluctuations. The proposed method provides a framework for estimating the macroscopic mechanical properties in other 2D nanostructures at finite temperatures.Graphical abstractImage 1
       
  • Mechanochemical synthesis of porous carbon at room temperature with a
           highly ordered sp2 microstructure
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): M.E. Casco, F. Badaczewski, S. Grätz, A. Tolosa, V. Presser, B.M. Smarsly, L. Borchardt Carbon nanostructures with a well-developed turbostratic sp2 structure and high porosity are synthesized at room temperature inside a planetary ball mill. The obtained carbons were analyzed in-depth by means of gas adsorption, wide-angle X-ray scattering (WAXS), Raman spectroscopy, and transmission electron microscopy (TEM). Our approach involves the solvent-free reaction between calcium carbide (CaC2) and hexachlorobenzene (C6Cl6) conducted under mechanochemical conditions. After certain mechanical activation time, the exothermic nature of the reaction (−492 kcal) provokes a combustion-like event that results in innocuous salt (CaCl2) and a carbonaceous material. Carbon with a high degree of structural order in the constituting graphene and the graphene stacks, possessing almost no internal surface, can be obtained after 5 min of milling time with a mass ratio CaC2/C6Cl6 of 0.9, while carbon exhibiting a surface area as high as 915 m2/g can be obtained after 2 h of milling time with a mass ratio CaC2/C6Cl6 of 5.1. WAXS results and TEM observations reveal a mixture of amorphous carbon and non-graphitic phases. Among the last one, spherical-shaped carbons and curved nanosized strips can be easily distinguished.Graphical abstractImage 1
       
  • Nanoscale infrared identification and mapping of chemical functional
           groups on graphene
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Cian Bartlam, Suzanne Morsch, Kane W.J. Heard, Peter Quayle, Stephen G. Yeates, Aravind Vijayaraghavan Chemical functionalisation of graphene and other 2-dimensional materials is a key step in realizing their full potential in various applications. There is a need for non-destructive and unambiguous identification of chemical groups and mapping of their distribution on such materials with nanoscale spatial resolution and at monolayer thicknesses. In this work, AFM-coupled infrared spectroscopy is used to analyse single layer reduced graphene oxide flakes that have been non-covalently functionalized with sulfonated pyrenes. We show this technique to be capable of distinguishing between the different pyrene moieties and mapping the sulfonate groups on a 1.7 nm functionalised monolayer of reduced graphene oxide with 32 nm spatial resolution. This technique is also shown to be sensitive to small changes in the sulfonate absorption spectra arising from chemical and surface effects, enough to distinguish between different functionalizing molecules even on materials with anisotropic thermal conductivity.Graphical abstractImage 1
       
  • Extremely large, non-oxidized graphene flakes based on spontaneous solvent
           insertion into graphite intercalation compound
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Jungmo Kim, Gabin Yoon, Jin Kim, Hyewon Yoon, Jinwook Baek, Joong Hee Lee, Kisuk Kang, Seokwoo Jeon Demand for an effective strategy for exfoliating layered materials into flakes without perturbing their intrinsic structure is growing. Herein, we introduce an effective fabrication method of large-sized non-oxidized graphene flakes (NOGFs) as a representative example of a general strategy using spontaneous insertion of exfoliating medium into a layered material. We fabricated a ternary graphite intercalation compound (t-GIC) with stoichiometry of KC24(THF)2, and analyzed its morphology and electronic structure through experimental and computational approach. Interactions between the t-GIC and aprotic organic solvents with different polarities were investigated, where a unique swelling behavior was observed with dimethyl sulfoxide (DMSO). Based on the analysis of the phenomena, we demonstrate facile exfoliation of the t-GIC in polyvinyl pyrrolidone (PVP)-DMSO solution for fabrication of highly crystalline and large-sized NOGFs. The lateral size of the NOGFs ranges over 30 μm, while the 98% having thickness below 10 layers. The NOGF film exhibits supreme electrical conductivity of 3.36 × 105 S/m, which is, to our best knowledge, the highest value for a thin conductive film made of graphene flakes.Graphical abstractImage 1
       
  • Identification and isolation of carbon oxidation and charge redistribution
           as self-discharge mechanisms in reduced graphene oxide electrochemical
           capacitor electrodes
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): M.A. Davis, H.A. Andreas While carbons are common electrode materials for electrochemical capacitors (ECs) owing to their abundance, affordability, and environmental compatibility, graphene is particularly desirable due to its high electronic conductivity and high surface area for double-layer charging. However, very little is known about graphene's self-discharge (SD) – the spontaneous potential loss that occurs when a device rests idle. Knowledge of SD mechanisms is key because this process limits EC applications and reliability. Herein, we show carbon oxidation and charge redistribution – charge movement to eliminate potential gradients within a material – are key SD mechanisms for reduced graphene oxide (rGO) in acidic-aqueous electrolytes. Differentiating between these phenomena proves challenging; both processes present similar SD profiles. To address this, a novel experimental protocol is developed which resets CR to hold this process constant; when applied, this protocol separates CR contributions from carbon oxidation. We thus can identify charge redistribution as the primary SD mechanism, with a smaller but important contribution (17% of original SD) from carbon oxidation. From this work, it is clear that rGO SD can be significantly reduced by oxidizing (achieved here by CV cycling) and by more fully charging the rGO material (achieved through repeated charge/SD cycles).Graphical abstractImage 1
       
  • Reducing lattice thermal conductivity in schwarzites via engineering the
           hybridized phonon modes
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Zhongwei Zhang, Shiqian Hu, Tsuneyoshi Nakayama, Jie Chen, Baowen Li The cage structure and low lattice thermal conductivity κL make the schwarzites a suitable candidate for building the host-guest system favorable for thermoelectric applications. In host-guest system, the guest atoms in cages play a crucial role for reducing κL. However, the underlying mechanism on the thermal conductivity reduction remains unclear. In this work, the authors unveil, through atomic simulations, the working principles of guest atoms in schwarzites by highlighting the relationship between thermal transport properties and rattling motions of guest atoms. It has been found that local vibration of the “on-center” guest atoms at low temperatures gives rise to a single hybridized mode, while the positions of guest atoms at high temperatures deviate severely from the center of cages yielding blue-shifted hybridized modes. These blue-shifted hybridized modes are responsible for the reduction of the phonon relaxation time in a wide range of frequencies. Based on these findings, the authors propose guidelines for reducing κL in schwarzites by properly tuning the frequency of one hybridized mode. Further reduction of κL can be achieved by simultaneously introducing multiple hybridized modes with different characteristic frequencies. This study provides insights to the controllable thermal transport properties in schwarzites by engineering the hybridized phonon modes.Graphical abstractImage
       
  • Historical experiment to measure irradiation-induced creep of graphite
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Anne A. Campbell This paper presents historical results of graphite irradiation-induced creep experiments that were performed at Oak Ridge National Laboratory from the 1950's to the 1970's. These experiments were performed at temperatures from 150°C to 1000 °C, and bend stresses ranging from 500 to 5000 psi (∼3.3–34.5 MPa). The experimental setup utilized in-situ measurement of specimen displacement, on-line applied stress control, and the ability to change stress during the experiment. The different stress conditions showed that the primary creep strain and the steady-state creep rates both have a linear stress dependence. The temperature range used in this work resulted in trends that have not be previously presented in the literature: 1) a linear dependence of primary creep strain on temperature, and 2) the shape of steady state creep rate versus temperature (see graphical abstract). The maximum dose in the specimens was 0.9 dpa, which is sufficient to achieve steady-state creep without the structural changes that alter the observed creep behavior. The results from this experiment provide evidence that dispels that the pinning-unpinning model describes the mechanism of irradiation creep in graphite. Instead these results suggest a dislocation climb mechanism is the probable mechanism for creep within the crystalline regions.
       
  • Semi-transparent biomass-derived macroscopic carbon grids for efficient
           and tunable electromagnetic shielding
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Zeping Chen, Da Yi, Bin Shen, Lihua Zhang, Xiaohui Ma, Yongyan Pang, Li Liu, Xingchang Wei, Wenge Zheng High-performance electromagnetic interference (EMI) shields are urgently needed due to the rapid development of modern electronics industry. Herein, biomass-derived highly conductive macroscopic carbon grids (MCGs) were fabricated through the carbonization of wood-pulp fabric matting. The resultant MCGs with thickness of ∼0.3 mm exhibited not only exceptional EMI shielding effectiveness (SE) of ∼20.3–45.5 dB positively related with their carbonization temperature or negatively associated with their empty grid size, but also semi-transparent characteristic with the transparency of ∼15%–56% originated from their grid-like configurations. Moreover, an accurate EM model was constructed for the SE simulation of the MCGs in the 3-D full-wave simulation. Furthermore, it is demonstrated that the EMI SE of double-layered MCG sample could be conveniently tuned by changing the interleaving degree of the stacked grids through tiny translational motion under constant thickness, showing potential for the design of EM attenuating devices with tunable performance.Graphical abstractImage 1
       
  • Oxidation of carbon by gaseous metal oxide: A multi-path mechanism study
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Quan Zhang, Minhua Zhang, Tomasz Wiltowski The adsorption of a gaseous (MoO3)3 cluster on a graphene ribbon and subsequent generation of COx was studied by density functional theory (DFT) method and compared with experimental results. The (MoO3)n -graphene complexes show interesting magnetic properties and potentials for nanodevices. A comprehensive analysis of plausible reaction mechanisms of CO and CO2 generation was conducted. Multiple routes to CO and CO2 formation were identified. The (MoO3)3 cluster shows negative catalytic effect for CO formation but does not increase the energy barrier for CO2 formation. CO2 is the primary product of the gaseous MoO3-carbon reaction. Mechanism of the homogenous MoO3 - CO reaction was studied and showed relatively low energy barriers. The DFT result accounts for key experimental observations of activation energy and product selectivity. The combined theoretical and experimental approach contributes to the understanding of the mechanism of reactions between carbon and metal oxide clusters.Graphical abstractImage 1
       
  • Hard carbons derived from green phenolic resins for Na-ion batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Adrian Beda, Pierre-Louis Taberna, Patrice Simon, Camélia Matei Ghimbeu Hard carbons have become recently one of the most promising classes of anode materials for sodium ion batteries (NIBs) owing to their high specific capacity and good cycling stability. Among the precursors used to prepare hard carbon, phenolic resins are of great interest due to their high carbon yield, however, their toxicity must be overcome. In this paper, we propose a green, simple and scalable procedure to obtain phenolic resins which by pyrolysis at high temperature (>1000 °C) result in eco-friendly hard carbons with low surface area, disordered structure and high carbon yield. The influence of several synthesis parameters (type of solvent, thermopolymerization/annealing temperature and gas flow) was studied to determine the impact on both phenolic resin and hard carbon characteristics. The synthesis time (12 h-3 days) was found to depend on the used solvent whereas the carbon yield (25–35%) on the cross-linking degree which could be controlled by adjusting both thermopolymerization temperature and atmosphere. The structure of the hard carbons mainly changed with the carbonization temperature (1100–1700 °C) while the texture of the material was sensitive to most of the studied parameters. Stable reversible capacity up to 270 mAhg−1 and 100% coulombic efficiency (CE) after few cycles are obtained, demonstrating the potential for Na-ion applications.Graphical abstractImage 1
       
  • Programmable actuating systems based on swimming fiber robots
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Hao Sun, Meng Liao, Jianfeng Li, Chao Zhou, Jue Deng, Xuemei Fu, Songlin Xie, Bo Zhang, Yizheng Wu, Bingjie Wang, Xuemei Sun, Huisheng Peng Microrobotics represents an important branch of robotics in the past decade, and demonstrates great potential in a broad range of applications such as targeted drug delivery, cell manipulation and bioimaging. However, it is rare while becomes critical to make integrated and programmable actuating systems with sophisticated and controllable architectures that are demanded for real applications. Here, we present a new family of bio-inspired programmable actuating systems assembled from carbon nanotube/platinum swimming fiber robots (SFRs). The SFRs demonstrate hetero-sectional structures that offer rapid and stable rotations in H2O2 solution. Similar to the building blocks like tentacle and spine of invertebrates, the SFRs are then assembled into programmable actuating systems that may move in rotation and translation or switch between them. As a general and effective strategy, this assembling methodology may also open up a new direction for microrobotics on system level.Graphical abstractA new family of bio-inspired programmable actuating systems have been made from carbon nanotube/platinum swimming fiber robots (SFRs). The SFRs demonstrate hetero-sectional structures that offer rapid and stable rotations in fuel solution. They can be assembled into programmable actuating systems that move in rotation and translation or switch between them. This assembling methodology may open up a new direction for microrobotics on system level.Image 1
       
  • Pomegranate-like molybdenum phosphide@phosphorus-doped carbon nanospheres
           coupled with carbon nanotubes for efficient hydrogen evolution reaction
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Ji-Sen Li, Xiao-Rong Wang, Jia-Yi Li, Shuai Zhang, Jing-Quan Sha, Guo-Dong Liu, Bo Tang Rational design and synthesis of low-cost electrocatalysts with high-performance is of urgency for hydrogen evolution reaction (HER). Herein, we report a facile synthetic approach to construct a pomegranate-like MoP@P-doped porous carbon nanospheres coupled with carbon nanotubes (CNTs) composite using metal-organic frameworks-CNTs hybrid as precursor, which was successfully employed as a robust electrocatalyst for the HER. Ascribed to the distinct nanostructure together with the synergistic coupling, the resultant composite exhibits highly efficient electrocatalytic performance, featured by a low onset overpotential of 75 mV, small Tafel slope of 55.9 mV dec−1, as well as long-term stability for 10 h, which is comparable or even superior to the best MoP-based catalysts toward HER up to now. More importantly, this strategy can provide a new route in the construction of highly efficient Pt-free electrocatalysts for energy conversion fields.Graphical abstractA pomegranate-like MoP@P-doped porous carbon nanospheres coupled with carbon nanotubes composite has been constructed using polyoxometalate-based metal-organic frameworks-carbon nanotubes hybrid as precursor through a facile carbonization and subsequent phosphidation process for the first time. Taking advantage of the rationally designed components and unique nanostructure, the catalyst shows remarkably enhanced electrocatalytic activity and long-term durability for the HER.Image 1
       
  • Hydrothermally reduced graphene oxide for the effective wrapping of sulfur
           particles showing long term stability as electrodes for Li-S batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): J.L. Gómez-Urbano, J.L. Gómez-Cámer, C. Botas, N. Díez, J.M. López del Amo, L.M. Rodríguez-Martinez, D. Carriazo, T. Rojo Lithium-sulfur batteries (Li-S) are identified as one of the most promising rechargeable energy systems due to their high theoretical capacity, high gravimetric energy density, low cost and low environmental impact. However, the insulating nature of sulfur and the migration of soluble polysulfides during discharge limit their practical application. In an attempt to mitigate these drawbacks here we report the preparation of a novel composite formed by hydrothermally reduced graphene oxide (HrGO) and submicrometer-sized sulfur particles. The role of HrGO is not restricted to enhance the electronic conductivity of the composite, but also sulfur wrapping in order to prevent polysulfides migration. Besides, the addition of polyvinylpyrrolidone (PVP) during the synthesis of the sulfur particles allows a greater control of their size and improves its homogeneous distribution within the composite. The material is tested as cathode for Li-S batteries showing reversible capacities over 900 mAh g−1 at a rate of 0.2 C and more than 650 mAh g−1 after 100 charge-discharge cycles. Moreover, this simplistic and environmentally friendly approach allow obtaining composites with sulfur loadings as high as 92 wt%, and large areal capacities up to 1.5 mAh cm−2.Graphical abstractImage 1
       
  • Structural integrity versus lateral size: Enhancing graphene-based film
           materials by reducing planar defects rather than flake boundary
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Hongwu Chen, Mingmao Wu, Chun Li Chemically modified graphene (CMG) bulk films have displayed a large potential in a plethora of applications. Incorporation of large CMG sheets was applied as the major strategy to improve both the electrical and mechanical properties of resulted film materials, whereas the low fabrication yield of high quality large building blocks severely obstruct its scalability. Herein, we evaluated the individual impact of sheet size and structural integrity of CMG building blocks on the performance of film materials, and results show that low structural defects density rather than large size dominates the enhancement of performance. Compared with large building blocks (average area 37.2 μm2), small ones (average area 1.3 μm2) with optimized structural integrity and also higher preparation yield formed films with even higher strength and conductivity (increased by 55% and 120%, respectively). Furthermore, the influence of structural integrity on the material performance was studied via detailed characterization. These results unequivocally impart the importance of structural integrity, and may give instruction on the rational design of materials with excellent performance.Graphical abstractImage 1
       
  • Taming the magnetoresistance anomaly in graphite
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Bruno Cury Camargo, Walter Escoffier At low temperatures, graphite presents a magnetoresistance anomaly which manifests as a transition to a high-resistance state (HRS) above a certain critical magnetic field Bc. Such HRS is currently attributed to a c-axis charge-density-wave taking place only when the lowest Landau level is populated. By controlling the charge carrier concentration of a gated sample through its charge neutrality level (CNL), we were able to experimentally modulate the HRS in graphite for the first time. We demonstrate that the HRS is triggered both when electrons and holes are the majority carriers but is attenuated near the CNL. Taking screening into account, our results indicate that the HRS possess a strong in-plane component and can occur below the quantum limit, being at odds with the current understanding of the phenomenon. We also report the effect of sample thickness on the HRS.Graphical abstractImage 1
       
  • Novel approach towards the synthesis of carbon-based transparent highly
           potent flame retardant
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Rahul V. Khose, Dattatray A. Pethsangave, Pravin H. Wadekar, Alok K. Ray, Surajit Some In this article, a novel and facile method is proposed to synthesize a highly effective carbon-based water dispersible flame retardant. This is the first report of carbon-based highly potent transparent flame retardant, which keeps the colour of the cloth intact. A functionalized flame retardant graphene quantum dots (FR-GQD) as a carbon-based material was synthesized using graphene oxide and phosphorous source through a hydrothermal treatment. As prepared transparent FR-GQD solution coated cotton cloth was found to maintain cloth's original colour. In a flame test, FR-GQD coated cloth emitted little smoke initially and after that, it failed to catch fire for more than 300 s and maintained its initial shape. Whereas the control cloth caught fire and burnt completely within 15 s. Flame retardant efficiency of the FR-GQD coated cloth was confirmed by detail flame tests such as limiting oxygen index (LOI), exposure to high heat flux (∼50 kW/cm2) and turbulent premixed flame at high temperature (∼1400 °C).The strength of FR-GQD coated cloth was determined using tensile strength test. This technique of synthesis and application of this water dispersed FR material may find a general approach towards the practical and eco-friendly application of non-toxic FR-GQD as transparent flame retardant.Graphical abstractImage 1
       
  • Additive-free electrode fabrication with reduced graphene oxide using
           supersonic kinetic spray for flexible lithium-ion batteries
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Seong Dae Kim, Jong-Gun Lee, Tae-Gun Kim, Kuldeep Rana, Jong Yeob Jeong, Jong Hyeok Park, Sam S. Yoon, Jong-Hyun Ahn Thin, lightweight, and flexible lithium-ion batteries (LIBs) are emerging as a promising power source for high-performance flexible electronics. However, their technological drawbacks have hindered the development of fully flexible electronics because of a lack of reliable electrode materials that combine superior electrochemical properties with mechanical flexibility. As a solution to this problem, we herein demonstrate an additive-free electrode fabrication process, where reduced graphene oxide (rGO) is coated onto a current collector using a supersonic kinetic spray technique (spray-rGO). The spray-rGO demonstrates outstanding mechanical and electrochemical properties compared to those of rGO electrodes fabricated using the conventional process. Moreover, despite being fabricated without any binders, spray-rGO exhibits high adhesion energy, which enables the fabrication of highly flexible electrodes with no structural deterioration or capacity degradation. This approach to fabricate additive-free flexible electrodes, which results in electrodes that satisfy other important criteria such as high rate capability, long-term cyclability, and facile and fast fabrication, is a prospective method for developing high-performance flexible LIBs.Graphical abstractImage 1
       
  • Steam engraving optimization of graphitic carbon nitride with enhanced
           photocatalytic hydrogen evolution
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Zhou Chen, Xiang Yu, Qiuhui Zhu, Tingting Fan, Qiuling Wu, Lizhong Zhang, Jianhui Li, Weiping Fang, Xiaodong Yi Graphitic carbon nitride (g-C3N4) has been extensively investigated as an efficient photocatalyst for water splitting. However, the intrinsic drawbacks of low surface area and poor charge separation efficiency seriously limit its practical applications in photocatalytic hydrogen evolution. Here, we designed an efficient nanorod-C3N4 photocatalyst by a versatile and scalable steam engraved protocol, which can produce higher surface area, enhanced crystallinity, reduced lattice defects, as well as meliorative energy band configuration. The engraved C3N4 exhibited a remarkably longer lifetime of charge carriers and a much higher photocatalytic hydrogen production rate than the pristine C3N4. The specific activity of the engraved C3N4 (87 μmol g−1h−1cm−2BET) is 10.4 times higher than that of pristine C3N4.Graphical abstractA steam-engraved method was used to construct rod C3N4 with higher surface area, reduced lattice defects, enhanced crystallinity, faster carriers transport and higher photo-drived hydrogen generation performance.Image 1
       
  • Improved microwave absorption properties by atomic-scale substitutions
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Yixing Li, Xiaofang Liu, Rongge Liu, Xueyong Pang, Yanhui Zhang, Gaowu Qin, Xuefeng Zhang To solve the electromagnetic impedance matching issue, microwave absorption materials are usually composed of magnetic and dielectric components with heterogeneous interfaces at micro/nanoscales. Herein we demonstrate an arc-discharging approach to optimize microwave absorption properties of magnetic@dielectric Fe@C nanocapsules by in-situ substituting nitrogen heteroatoms in graphitic layers. By increasing the nitrogen content, we find that the electromagnetic properties can be effectively tuned, presenting the decreased transmission, the increased absorbance and the slight change for the reflection efficiencies. Experimental and theoretical results reveal that nitrogen dopants result in the atomic-scale symmetry breaking, inducing the separation of space charge at nitrogen-substituted sites, which play a role of electric dipole for the electromagnetic polarization. The present study has important significance in understanding the structural origin of microwave absorption, and meanwhile provides an effective way for designing microwave absorbents at atomic-scale.Graphical abstractImage 1
       
  • Nanostructure evolution and reactivity of nascent soot from inverse
           diffusion flames in CO2, N2, and He atmospheres
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Yaoyao Ying, Dong Liu The micro and nanostructure evolutions and reactivity of nascent soot from n-butanol-doped ethylene inverse diffusion flames in CO2, N2, and He atmospheres were studied and compared. The thermophoretic sampling technique was employed to capture soot particles directly at different positions along the flame boundary. Transmission electron microscopy was applied to obtain the particle morphology evolution. Moreover, high-resolution transmission electron microscopy analysis, Raman spectroscopy analysis, thermogravimetric analysis, and X-ray photoelectron spectroscopy were performed to study the nanostructure and oxidation reactivity of soot from the quartz plate sampling. It was found that soot inception rate was reduced in CO2 atmosphere, indicating CO2 could inhibit soot formation through inception process. However, He promoted soot formation since the soot agglomerate amount was larger than those in flames with CO2 and N2. High correlations were found between soot nanostructure and reactivity. The soot from CO2 atmosphere had shortest fringe length and largest fringe tortuosity related with highest oxidation reactivity. On the contrary, soot from He diluted flame exhibited prevalent fullerenic-like nanostructures with evident large or small shells, and also had a higher carbonization degree resulting in lower oxidation reactivity. The surface oxygen content related to soot oxidation reactivity.Graphical abstractImage
       
  • Multifunctional fluorescent “Off-On-Off” nanosensor for Au3+ and S2−
           employing N-S co-doped carbon–dots
    • Abstract: Publication date: November 2018Source: Carbon, Volume 139Author(s): Vinay Sharma, Navpreet Kaur, Pranav Tiwari, Anoop K. Saini, Shaikh M. Mobin Out of the plethora of sensors being developed using carbon dots, the use of green alternatives with the potential of multi-functionality is still in its infancy. In view of this, the present work shows the use of Rosa indica derived heteroatom i.e. nitrogen and sulfur co-doped rose carbon dot (N-S@RCD) for dual fluorescence based sensing of multi-analytes. The N-S@RCD shows interesting fluorescence turn “off-on-off” response towards S2− and Au3+ with limit of detection (LOD) 92.4 nM and 63.1 nM, respectively. To the best of our knowledge, this is first report on direct “Turn-on” of c-dots with S2− ions without any intermediate c-dot–quencher complex. Further, the bioimaging and flow cytometry studies revealed the potential of live cell imaging, intracellular sensing and cytocompatibility of N-S@RCD. The hemocompatibility of N-S@RCD was also investigated for potential in vivo applications. Moreover, the “off-on-off” fluorescence behaviour was used to construct molecular logic gates which simulate single input logic “YES” and multi-input “INHIBIT” logic system.Graphical abstractImage 1
       
  • Tuning hydroxyl groups for quality carbon fiber of lignin
    • Abstract: Publication date: Available online 11 July 2018Source: CarbonAuthor(s): Qiang Li, Mandar T. Naik, Hao-Sheng Lin, Cheng Hu, Wilson K. Serem, Li Liu, Pravat Karki, Fujie Zhou, Joshua S. Yuan Lignin-based carbon fiber is struggling to apply into industry, due to its low mechanical performance. Our concept is that lignin chemical features impact its interactions with guest molecules and crystallite formation in carbonization, and thus carbon fiber mechanical performance. We recently demonstrated that fractionating lignin polymers according to their molecular weight enhanced the elastic modulus, but the process used costly enzyme and dialysis tubes and difficult to scale up. Here we present a simple one-pot lignin processing technology that only precipitate lignin into aqueous acid. Our approach is based on manipulating lignin hydroxyl groups, which improves multiple hydrogen bonding and linear chemical linkages to enhance molecular interactions and thereby carbon fiber crystallite structures. Carbon fiber out of the presented technique has elastic modulus comparable with that derived from the costly enzymatic and dialysis fractionation methods, and even the traditional PAN-based carbon fibers. The presented technology offered a route to make quality lignin-based biorenewable carbon fiber by regulating fiber precursor at molecular level, which has a broad application in upgrading industrial lignin waste of paper-making industry and lignocellulosic biorefinery.Graphical abstractImage 1
       
  • Z-scheme reduced graphene oxide/TiO2-Bronze/W18O49 ternary heterostructure
           towards efficient full solar-spectrum photocatalysis
    • Abstract: Publication date: Available online 11 July 2018Source: CarbonAuthor(s): Changchao Jia, Xiao Zhang, Katarzyna Matras-Postolek, Baibiao Huang, Ping Yang Z-scheme reduced graphene oxide (rGO)/TiO2-bronze (TiO2-B)/W18O49 photocatalyst consisted of rGO, super-thin TiO2-B nanosheets, and W18O49 nanofibers was fabricated by a two-step solvothermal synthesis route. The TiO2-B nanosheets were tightly attached on rGO firstly. W18O49 nanowires were then grown on rGO/TiO2-B. Precursors and reaction conditions play important roles for getting the optimal microstructure. The ternary photocatalyst is able to absorb sunlight ranging from ultraviolet to near infrared regions, which makes full use of light for efficiently photocatalytic degrading organic pollutants. The light absorption intensity and photon-generated carrier transfer efficiency are both improved with adding rGO. The localized surface plasmon resonance effect arose from the nonstoichiometric W18O49 is in favour of the absorption range of the rGO/TiO2-B/W18O49 composite broadening to near infrared light range. The photocatalytic mechanism of Z-scheme rGO/TiO2-B/W18O49 composite was verified by an electron spin resonance test. The conduction band of TiO2-B and the valence band of W18O49 are used in the photocatalytic degradation of rhodamine B, facilitating the efficient separation of photogenerated carriers. The rGO/TiO2-B/W18O49 heterostructure exhibits an excellent photocatalytic performance under full solar-spectrum irradiation. The result may represent a new strategy for the construction of nanocomposites with suitable band structure in the efficient application of full solar light.Graphical abstractZ-scheme rGO/TiO2-B/W18O49 ternary heterojunctions were successfully prepared, and the structure exhibited an excellent photocatalytic activity under UV–Vis–Near infrared light.Image 1
       
 
 
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