Nano-sized cerium-titanium pyrophosphates Ce1-xTixP2O7 (with x = 0, 0.2, 0.5, 0.7, 0.9, and 1.0) were obtained by grinding a mixture of Ce(SO4)2·4H2O, Ti(SO4)2, and Na4P2O7·10H2O in the presence of surfactant PEG-400 at room temperature, washing the mixture with water to remove soluble inorganic salts, and drying at 100℃. The products and their calcined samples were characterized using ultraviolet-visible spectroscopy (UV-vis), thermogravimetry and differential thermal analyses (TG/DTA), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM). The results show that nano-sized Ce1-xTixP2O7 behave as an excellent UV-shielding material. Thereinto, the CeP2O7 has the most excellent UV-shielding effect, and the amorphous state of Ce0.8Ti0.2P2O7 can keep at a higher temperature than CeP2O7. Therefore, the stabilization of the amorphous state of the cerium pyrophosphates was carded out by doping titanium. This stabilization is a significant improvement, which enables to apply these amorphous pyrophosphates not only to cosmetics and paints, but also plastics and films.
WU Wenwei FAN Yanjin WU Xuehang LIAO Sen HUANG Xiufu LI Xuanhai
Nanocrystalline NH4ZrH(PO4)2·H2O was obtained by grinding ZrOC12·8H2O and (NH4)2HPO4 in the presence of surfactant PEG-400 via solid-state reaction at room temperature. The product NH4ZrH(PO4)2·H2O and its product of thermal decomposition were characterized using thermogravimetry and differential thermal analyses (TG/DTA), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM). Nanocrystalline NHaZrH(PO4)2·H2O with an average particle size of 17 nm was obtained when the product was kept at80℃ for 3 h. Its crystalline framework was stable at temperatures below 250℃. In addition, the catalytic performance of NH4ZrH(PO4)2·H2O in the synthesis of butyl acetate was investigated. The results show that NH4ZrH(PO4)2·H2O behaved as an excellent heterogeneous catalyst in the synthesis of butyl acetate.
WU Wenwei LAI Shuibin WU Xuehang LIAO Sen HOU Shengyi