Preparation And Photocatalytic Properties Of A（Ca, Ba, Sr）TiO₃ Particles With Various Morphology

Perovskite-type oxide (ABO3), a class of functio nal materials with colorful structure and performance, while changing the elements of A bit and B bit, its structure and performance will change also. Because of the properties of the materials are significantly influenced by the structure, the researches on the controllable morphology and size of the perovskite-type oxide materials have been a hot spot. CaTiO3, BaTiO3 and SrTiO3 as the representive compounds of the perovskite-type oxide, are important photocatalytic material and electronic ceramics, and therefore are widely used in the sensors, photocatalytic and other research area This paper mainly focused on the preparation of perovskite A(Ca, Ba, Sr)TiO3 particle, and their structures and morphologies were characterized by X-ray diffraction(XRD), Transmission electron microscopy (TEM), Scanning electron microscopy(SEM), respectively. The photocatalytic activity of perovskite-type oxides A(Ca, Ba, Sr)TiO3 were examined by photcatalytic activity. The result were as follows:(1) Low-cost commercial TiO2 as titanium source, CaCl2 as the calcuium source, CaTiO3 particles were prepared by a salt solvent method, compound CaCl2 and Ca(NO3)2 as molten salt, the square and spherical shape CaTiO3 particles were prepared in 850℃ for 3 hour and 600℃ for 12 hour respectively. With composite alkali for molten salt, reaction at 180℃ for 1 hour, and subsequent calcination received about 50 nm size, spherical better dispersibility CaTiO3 particle.(2) The compound alkali is used as solvent, TiO2 as raw materials to prepare the titanate for the first time. Titanate as titanium source, the CaTiO3 particles were prepared by hydrothermal methed. Through changing the hydrothermal temperature, concentration of NaOH, we obtained the butterflies, tubular, sheet morphology of the shape CaTiO3 particles. At the same time, studying the effect of morphology and structure on the photocataplytic properties. The studies suggest that the CaTiO3 particles with the shape of butterflies showed the best photocatalytic activity.(3) The obove preparation method is also used to prepare BaTiO3 and SrTiO3 particles. The round-likely roundness, regular square BaTiO3 particles and the hollow SrTiO3 particles are obtained by changing NaOH concentrations, reaction time and temperature. and then studied their photocatalytic properties. The studies suggest that regular square BaTiO3 particles and the hollow SrTiO3 particles have the better photocataplytic activities.