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CuO/TiO2 composites were prepared by the impregnation method, in which TiO2 nanosheets and nanorods are used as the precursors, respectively. We investigated the effect of the TiO2 surface structure on the activity and recyclability of the photocatalysts. The hydrogen production activities were tested in a 3 mol L−1 methanol aqueous solution under UV-light irradiation. After deposition of Pt, both Pt@CuO/TiO2 samples displayed higher hydrogen production activities than the Pt/TiO2 samples. The results reveal that the TiO2 sheet-based samples display higher hydrogen production activities and stability than the TiO2 rod-based ones. It is proposed that a more stable p-n heterojunction form at the interface between CuO and TiO2 nanosheets owing to the strong interaction of CuO with the {0 0 1} facets of the TiO2 sheets, which significantly refrains the recombination rate of electrons and holes. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the LiFePO4 nanorods are synthesized in an ionic liquid (IL) in the presence of a surfactant. The samples are characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, electron diffraction and nitrogen adsorption. The as-obtained LiFePO4 nanorods in the IL have the diameter of about 200nm and the length of 1–2μm; but the aggregated LiFePO4 microparticles are obtained in the aqueous solution. The results show that a higher temperature and a longer duration are needed in the IL than in the aqueous solution for the formation of LiFePO4; that both IL and the surfactant play the key roles in the formation of LiFePO4 nanorods. Furthermore, their charge and discharge properties are investigated. The LiFePO4 nanorods show a higher discharge capacity (150 at 1C rate) and a higher rate capability than the aggregated particles (133mAhg−1). The adopted IL approach may provide a “green” route to achieve excellent battery materials. [Copyright &y& Elsevier]

Abstract: The highly porous Co3O4 nanorods are prepared by a simple hydrothermal method, in which CO(NH2)2 is employed as precipitating agent, and K60 (PVP, polyvinylpyrrolidone) is used as surfactant to improve the stability of the nanoparticles. For comparison, the bulk Co3O4 is prepared by thermal decomposition of cobalt nitrate. The samples are characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (ED), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption, Thermogravimetric analysis (TG), H2-temperature programmed reduction (TPR), CO-, CH4-, and O2-temperature programmed desorption (TPD). The catalluminescence (CTL) and catalytic properties of the samples are investigated extensively. The results show that the Co3O4 nanorods are composed of nanoparticles, and have a large number of pores with a narrow pore size distribution (1.5–7nm). Compared with the bulk Co3O4, the porous nanorods have a higher CTL intensity of CO oxidation, and a higher activity of CH4 combustion especially at a higher gas hourly space velocity (GHSV), which has been ascribed to its porous structure and larger surface area. [Copyright &y& Elsevier]