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β-Ga2O3 nanostructures are attractive wide-band-gap semiconductor materials as they exhibit promising photoelectric properties and potential applications. Despite the extensive efforts on β-Ga2O3 nanowires, investigations into β-Ga2O3 nanotubes are rare since the tubular structures are hard to synthesize. In this paper, we report a facile method for fabricating β-Ga2O3 nanotubes using pre-synthesized GaSb nanowires as sacrificial templates. Through a two-step heating-treatment strategy, the GaSb nanowires are partially oxidized to form β-Ga2O3 shells, and then, the residual inner parts are removed subsequently in vacuum conditions, yielding delicate hollow β-Ga2O3 nanotubes. The length, diameter, and thickness of the nanotubes can be customized by using different GaSb nanowires and heating parameters. In situ transmission electron microscopic heating experiments are performed to reveal the transformation dynamics of the β-Ga2O3 nanotubes, while the Kirkendall effect and the sublimation process are found to be critical. Moreover, photoelectric tests are carried out on the obtained β-Ga2O3 nanotubes. A photoresponsivity of ~25.9 A/W and a detectivity of ~5.6 × 1011 Jones have been achieved with a single-β-Ga2O3-nanotube device under an excitation wavelength of 254 nm. [ABSTRACT FROM AUTHOR]

Al-Ti-C master alloys were fabricated by using aluminum melt reaction method with graphite powders (GPs) or carbon nanotubes (CNTs) as carbon source. The microstructure formation during the reaction process was analyzed. The α-Al grain refinement abilities of the master alloys were checked. The results demonstrate that the TiC particles form mainly through the reaction between the solid C (GPs or CNTs) and the solute Ti. Using CNTs as the carbon source can significantly enhance the recovery rate of carbon and promote the formation of Al-Ti-C master alloy with a well dispersed microstructure and high α-Al grain refining ability. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) is considered as a powerful technique to synthesize novel electrode materials for lithium-ion batteries (LIBs), because not only the compositions can be specifically designed to achieve higher battery performances, but also the materials can be deposited on various substrates for different purposes. Herein, a novel design of active material/electrolyte mixture electrode, i.e., titanium dioxide/lithium phosphate (TLPO) nanocomposite, has been successfully developed by ALD and deposited on carbon nanotube substrates (CNTs@TLPO) at 250 °C, by combining the ALD recipes of TiO2 and lithium phosphate (LPO). In the nanocomposite, TiO2 forms anatase nanocrystals, embedded in a matrix of amorphous lithium phosphate. CNTs@TLPO has been examined as an anode material for LIBs, exhibiting a similar electrochemical response as anatase TiO2 in the cyclic voltammetry testing. CNTs@TLPO presents an outstanding capacity of 204 mA h g−1 upon 200 cycles in charge and discharge cycling measurements, as well as a significantly improved rate capability compared with ALD deposited TiO2 on CNTs without LPO ALD cycles. This work shows that the in situ addition of solid-state electrolyte (e.g., lithium phosphate), which introduces higher Li+ ionic conductivity, is an efficient way to achieve high-performance electrode materials for LIBs by ALD. [ABSTRACT FROM AUTHOR]

An aligned and laminated sulfur-absorbed mesoporous carbon/carbon nanotube (CNT) hybrid cathode has been developed for lithium-sulfur batteries with high performance. The mesoporous carbon acts as sulfur host and suppresses the diffusion of polysulfide, while the CNT network anchors the sulfur-absorbed mesoporous carbon particles, providing pathways for rapid electron transport, alleviating polysulfide migration and enabling a high flexibility. The resulting lithium-sulfur battery delivers a high capacity of 1226 mAh g−1 and achieves a capacity retention of 75 % after 100 cycles at 0.1 C. Moreover, a high capacity of nearly 900 mAh g−1 is obtained for 20 mg cm−2, which is the highest sulfur load to the best of our knowledge. More importantly, the aligned and laminated hybrid cathode endows the battery with high flexibility and its electrochemical performances are well maintained under bending and after being folded for 500 times. [ABSTRACT FROM AUTHOR]

A facile method was developed for the detection of Brilliant Blue FCF (BB FCF) (E133), a synthetic soluble colorant in common beverages. The method is based on a new composite of multi-walled carbon nanotube (MWCNT)-graphite oxide (GO)-room temperature ionic liquids (MWCNT/GO-RTIL) of 1-butyl-3-methylimidazolium hexafluorophosphate with high dispersibility and strong conductivity. Differential pulse stripping voltammetry (DPSV) and the MWCNT/GO-RTIL composite-modified glassy carbon electrode (GCE) were used to determine the BB FCF in this work. Under the optimum experimental conditions, the oxidation current of BB FCF was proportional to its concentration in two linear ranges, from 6.34 μg kg−1to 7.93 × 102 μg kg−1and 7.93 × 102 μg kg−1to 7.93 × 103 μg kg−1. The detection limit was down to 3.01 μg kg−1at signal-to-noise ratio of 3. Also, this method has been successfully applied in the determination of BB FCF in common beverage samples, including RIO cocktail, Bacardi Breezer and Reinnbow rum dinks. The assay results of BB FCF in drink samples obtained by the proposed method were in a good agreement with the reference values detected by high performance liquid chromatography (HPLC). The proposed method provided a useful tool for the assay of BB FCF in drink samples. [ABSTRACT FROM PUBLISHER]

Inspired by the fantastic and fast-growingwearable electronicssuch as Google Glass and Apple iWatch, matchable lightweight and weaveableenergy storage systems are urgently demanded while remaining as abottleneck in the whole technology. Fiber-shaped energy storage devicesthat can be woven into electronic textiles may represent a generaland effective strategy to overcome the above difficulty. Here a coaxialfiber lithium-ion battery has been achieved by sequentially windingaligned carbon nanotube composite yarn cathode and anode onto a cottonfiber. Novel yarn structures are designed to enable a high performancewith a linear energy density of 0.75 mWh cm–1. Awearable energy storage textile is also produced with an areal energydensity of 4.5 mWh cm–2. [ABSTRACT FROM AUTHOR]

Abstract: As an important part of dissolved organic matter (DOM), low molecular weight organic acids (LOAs) may play a key role in the process for DOM stabilizing carbon nanomaterials (e.g. C60) suspensions in aquatic environment. In addition, both LOAs and C60 have been detected in the troposphere and therefore have a chance to interact with each other in the gaseous phase. However, the mechanism for LOAs–C60 interactions and their environmental implications need further investigations. In this study, molecular dynamics (MD) simulation was employed to investigate the interactions between both neutral and ionic LOAs with C60 in vacuum and water. The results showed that the adsorptions of all LOAs on C60 in energy are favorable, and the aromatic acids have stronger interactions with C60 than the aliphatic acids in vacuum and water. The interaction energies (E int) of the LOA anions with C60 were weaker than those of their corresponding neutral LOA molecules. The models were also developed to predict and interpret E int based on the results from MD simulations. Dispersion, induction and hydrophobic interactions were found to be the dominating factor in E int. These findings indicate that cost-efficient MD simulation can be employed as an important tool to predict the adsorption behavior of LOAs on carbon nanomaterials. [Copyright &y& Elsevier]

Abstract: In this paper, an acetylcholinesterase (AChE)/dendrimers polyamidoamine (PAMAM)-Au/Carbon nanotubes (CNTs) multilayer modified electrode based on LbL self-assembled technique was employed in the detection of carbofuran in samples. The configuration of the nanostructure on the electrode provided a favorable environment to the immobilization of AChE. The modified films also improved the electrocatalytic characteristics and electron transfer speed between the films and the surface of electrode. The PAMAM-Au nanoparticles were characterized by SEM and UV–VIS methods. A set of experimental conditions were also optimized for the detection of the pesticides. A linear response over carbofuran concentration in the range of 4.8×10−9 M to 0.9×10−7 M was exhibited with a detection limit of 4.0×10−9 M. The biosensor showed high sensitivity, good stability and reproducibility with promising application. [Copyright &y& Elsevier]

In this paper, two carbon nanotube (CNT) nanofillers, namely the multi-walled carbon nanotubes (MWCNTs) and the carboxyl-modified MWCNTs (cMWCNTs), were introduced into the polydimethylsiloxane (PDMS) matrix respectively, in order to produce the PDMS composites with reinforced anti-biofouling properties. The anti-biofouling capacity of the silicone-based coatings, including the unfilled PDMS (P 0 ), the MWCNTs-filled PDMS (P M ) and the cMWCNTs-filled PDMS (P C ), was examined via the field assays conducted in Weihai, China. The effect of different silicone-based coatings on the dynamic variations of the pioneer microbial-community diversity was analyzed using the single-strand conformation polymorphism (SSCP) technique. The P M and P C surfaces have exhibited excellent anti-biofouling properties in contrast to that of the PDMS surface, with extremely low attachment of the early colonizers, such as juvenile invertebrates, seaweeds and algae sporelings. The P M and P C surfaces can effectively prevent biofouling for more than 12 weeks. These combined results suggest that the incorporation of MWCNTs or cMWCNTs into the PDMS matrix can dramatically reinforce its anti-biofouling properties. The SSCP analysis reveals that compared with the PDMS surfaces, the P M and P C surfaces have strong modulating effect on the pioneer prokaryotic and eukaryotic communities, particularly on the colonization of pioneer eukaryotic microbes. The significantly reduced pioneer eukaryotic-community diversity may contribute to the weakening of the subsequent colonization of macrofoulers. [ABSTRACT FROM AUTHOR]

Printing is rapidly emerging as a novel fabrication technique for energy storage and conversion technologies. As nanostructured carbons replace traditional materials in energy devices due to their unique structures and properties, intensive research efforts have focused on developing methods to print these new materials. Inkjet printing, screen printing, transfer printing, and 3D printing are increasingly used to print carbon nanomaterials. After a brief introduction of the basic operating principles of each of these techniques, methods for printing fullerenes, graphene, carbon nanotubes, carbon black, and activated carbon are reviewed. Subsequently, the applications of printing techniques for fabricating batteries, supercapacitors, fuel cells, and solar cells are discussed, followed by a perspective on the current challenges and future outlook of printing nanostructured carbon materials for these devices. [ABSTRACT FROM AUTHOR]

In the present work, a novel strategy based on new carbon nanotube (CNT) and polypyrrole (ppy) composite modified electrode for the simultaneous determination of the isomers of Amaranth (E123) and Ponceau 4R (E124) was proposed. Due to the increasing dispersibility and effective surface area of the CNT caused by decoration of ppy to the CNT, the proposed electrode exhibited excellent electrochemical sensitivity and high selectivity toward the oxidation of Amaranth and Ponceau 4R. The linear response ranges for Amaranth and Ponceau 4R were 5.0 × 10 −9 M–5.0 × 10 −7 M, and 8 × 10 −9 M–1 × 10 −6 M and corresponding detection limits as low as 5.0 × 10 −10 M and 1.0 × 10 −9 M, respectively. This proposed method was successfully applied in the detection of Ponceau 4R and Amaranth in fruit drink samples. [ABSTRACT FROM AUTHOR]

Abstract: Dissolved organic matter (DOM) plays a critical role in the transport of carbon nano-particles (e.g. C60) in the aquatic environment. However, the mechanism for C60-DOM interactions and its environmental implications needs further investigations. In this study, the interaction of C60 with relevant reference compounds of DOM (DOMR) is computationally simulated by molecular mechanics and density functional theory (DFT). All the C60-DOMR complexes are firstly optimized by classical annealing, and then DFT using the Dmol3 code. The adsorption energies of C60 on DOMR were computed. The computed electrostatic potential indicates that DOMR are electron acceptors in the C60-DOMR complexes, and the thermodynamic calculations indicate that electrostatic interaction is the dominant driving force for the C60-gallic acid complexation process in water. The presence of DOMR increases the apparent water solubility of C60. It is also observed that the C60 apparent water solubility decrease with the increase of the energy gaps of frontier molecular orbitals (E LUMO–E HOMO) for each C60-DOMR complex. These findings indicate that computational simulation is an important tool for predicting the behavior and fate of carbon nano-particles in the aquatic environment. [Copyright &y& Elsevier]

Abstract Electrocatalytic active species, for example, metal sulfides, have been widely combined with carbon nanomaterials for enhanced performance because of the synergetic effect arising from the interaction between different components. However, the binding between metal sulfides and carbon nanomaterials, which plays a key role in determining their interaction, has not been clearly elucidated. Herein, we reported the sulfur bridges between sulfur-doped carbon nanotubes (S-CNTs) and Co 9 S 8 nanoparticles and their significant effect on the practical electrochemical performance. Compared to the physically mixed composites, the one with sulfur bridges between CNTs and Co 9 S 8 shows much better performance in terms of oxygen evolution (overpotential of 0.331 V at 10 mA cm−2) and oxygen reduction (half-wave potential of 0.810 V). Demonstrating that the sulfur bridges facilitate fast electron hopping from conductive support to active species, thus contributing to the outstanding electrochemical performance. Moreover, a rechargeable Zn-Air battery based on our electrocatalyst with strong sulfur bridges delivers an outstanding performance in terms of ORR and OER bifunctional performances. The clear understanding of the sulfur bridges between CNTs and Co 9 S 8 is believed to shed substantial light on the development of other high-performance electrocatalysts. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

LiFePO4 is deposited on CNTs (CNT: carbon nanotube) by atomic layer deposition at 300 °C to form LiFePO4/CNT nanocomposite using ferrocene, ozone, trimethylphosphate, water, and LiO-tBu as precursors. [ABSTRACT FROM AUTHOR]