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Abstract: Spherical nano-sized YSZ (yttria stabilized ZrO2) powders were successfully synthesized via a reverse microemulsion system. The water droplets in the microemulsion system of yclohexane/water/span85/Triton X-100/hexyl alcohol can act as the nano-reactors which solubilize zirconium oxychloride and ammonia water separately. The minute original reactors are favor to the formation of nano-sized spherical YSZ powders and the dispersibility of the powders can be controlled effectually by adjusting the weight ratio of the LiNO3 molten salt to the precursor. The phase transformation from cubic to monoclinic starts at and 500 °C and finally monoclinic and cubic phase with increased crytallinity coexist at 800 °C. The effect of LiNO3 molten salt in the formation of YSZ powders was also discussed. [Copyright &y& Elsevier]

Abstract: TiF4 and Ti(OEt)4 were used as titanium source to prepare Ti-containing MCM-48 by hydrothermal method, respectively. The products were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, UV–visible absorption spectra and X-ray absorption near edge structure (XANES). The analysis results indicated that the types of titanium sources have great effects on the formation of Ti-MCM-48. Using TiF4 as precursor, Ti-containing silica with cubic mesoporous structure can be synthesized simply and quickly. The UV–visible absorption spectra and Ti K-edge XANES spectra confirmed that the isolated tetrahedrally-coordinated titanium oxide moieties were highly dispersed in the framework of MCM-48 by using TiF4 as titanium source. [Copyright &y& Elsevier]

Abstract: Au/CeO2 nanorods of ~15 nm in diameter and 100–400 nm in length have been synthesized through an efficient and simple method, and subsequently the novel low-temperature catalytic performance of Au/CeO2 nanorods for CO oxidation is found. The composites are characterized by transmission electron microscopy, X-ray diffraction as well as X-ray photoelectron spectroscopy. It is found that the Au nanoparticles with an average diameter of 8 nm are distributed uniformly on the surface of CeO2 nanorods. The possible formation mechanism of Au/CeO2 nanorods has been discussed. The T50 depicting the catalytic activity for CO oxidation can reach 62.1 °C, which is much lower than that of CeO2 nanorods or Au/CeO2 powders. In addition, Au/CeO2 nanorods exhibit excellent stability as catalysts for CO oxidation. [Copyright &y& Elsevier]