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Abstract: A TiO2 organic sol was synthesised for the preparation of a compact TiO2 layer on fluorine-doped tin oxide (FTO) glass by a dip-coating technique. The resultant thin film was used for the fabrication of dye-sensitized solar cells (DSSCs). The compact layer typically has a thickness of ca. 110nm as indicated by its SEM, and consists of anatase as confirmed by the XRD pattern. Compared with the traditional DSSCs without this compact layer, the solar energy-to-electricity conversion efficiency, short-circuit current and open-circuit potential of the DSSCs with the compact layer were improved by 33.3%, 20.3%, and 10.2%, respectively. This can be attributed to the merits brought by the compact layer. It can effectively improve adherence of TiO2 to FTO surface, provide a larger TiO2/FTO contact area, and reduce the electron recombination by blocking the direct contact between the redox electrolyte and the conductive FTO surface. [Copyright &y& Elsevier]

A simple and facile two-step method, including electrophoretic deposition and chemical bath deposition strategies, has been used to fabricate a novel interlocking g-C 3 N 4 /CdS photoanode on conductive substrate. Integrating a large area of intercontact g-C 3 N 4 /CdS heterojunction with an intimate connection between the photocatalysts and the substrate, the separation and migration of the photogenerated carriers by g-C 3 N 4 and CdS are significantly improved, and the internal resistance of the photoanode is effectively reduced. The optimal g-C 3 N 4 /CdS photoanode exhibits an excellent visible light photocurrent density of 5.4 mA cm -2  at 0.0 V bias ( vs. Ag/AgCl) and the photoelectrochemical H 2 production rate reaches 81.1 μmol h -1  cm -2 . Moreover, the stability of this interlocking g-C 3 N 4 /CdS photoanode not only reflects in a 9-hour long time recycling photoelectrochemical H 2 production test, but also in an outstanding steady structure which even be stabilized in an ultrasonic treatment. The present study provides a practical and convenient technique to develop such an earth abound and low-cost CdS/C 3 N 4 photoanode which can be used for high efficiency and stable photoelectrochemical solar energy conversion. [ABSTRACT FROM AUTHOR]

Zinc oxide wrapped sulphur/carbon nanotubes (ZnO@S/CNT) and nickel hydroxide wrapped sulphur/carbon nanotubes (Ni(OH) 2 @S/CNT) nanocomposites are prepared using a simple, low cost and scalable ball-milling method. As the cathodes in Li-S batteries, the as-prepared ZnO@S/CNT composite illustrates a superior high initial capacity of 1663 mAh g −1 at a charge/discharge rate of 160 mA g −1 , and maintains a reversible capacity at approximately 942 mAh g −1 after 70 cycles. While for Ni(OH) 2 @S/CNT composites, its initial capacity is also as high as 1331 mAh g −1 , but a poorer cycling stability is presented. When the charge/discharge current is increased to 1600 mA g −1 , a high reversible capacity of 698 mAh g −1 after 200 cycles still can be obtained for the ZnO@S/CNT composite, far better than that of Ni(OH) 2 @S/CNT composites. The better cycling performance and high discharge capacity can be attributed to the strong interactions between ZnO and S x 2− species, which is verified by the density functional theory (DFT) calculation result that the ZnO exhibits a higher adsorption energy for Li 2 S 8 than the Ni(OH) 2 . [ABSTRACT FROM AUTHOR]

The high rate applications such as electric vehicles of the traditional lithium ion batteries (LIBs) are commonly limited by their insufficient electron conductivity and slow mass transport of lithium ions in bulk electrode materials. In order to address these issues, in this work, a simple and up-scalable wet-mechanochemical (wet-ball milling) route has been developed for fabrication of amorphous porous TiO 2 @nitrogen doped graphene (TiO 2 @N-G) nanocomposites. The amorphous phase, unique porous structure of TiO 2 and the surface defects from nitrogen doping to graphene planes have incurred surface controlled reactions, contributing pseudocapacitance to the total capacity of the battery. It plays a dominant role in producing outstanding high rate electrochemical performance, e.g., 182.7 mAh/g (at 3.36 A/g) after 100 cycles. The design and synthesis of electrode materials with enhanced conductivity and surface pseudocapacitance can be a promising way for high rate LIBs. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotube (CNT) and TiO2 nanofibre composite films are prepared and used as anode materials for lithium ion batteries (LIBs) without the use of binders and conventional copper current collector. The preliminary experimental results from X-ray diffraction, scanning electron microscopy and transmission electron microscopy suggest that the TiO2 nanofibres were well-dispersed and interwoven by the CNTs, forming freestanding, bendable and light weighted composite. In comparison with TiO2 nanofibre based LIBs, the CNTs could significantly improve the battery performance due to their high conductivity property and 3D network morphology. In both 1–3V and 0.01–3V testing voltage ranges, the as-prepared composites show excellent reversible capacity and capacity retention. The superior lithium storage capacity of the CNT/TiO2 composite was mainly attributed to dual functions of the CNTs – the CNTs not only provide conductive networks to assist the electron transfer but also facilitate lithium ion diffusion between the electrolyte and the TiO2 active materials by preventing agglomeration of TiO2 nanofibres. This work demonstrates that the CNT–TiO2 composite film could be one type of potential electrode material for large-scale LIB applications. [Copyright &y& Elsevier]