煅烧温度对TiO_2中空微球光催化性能的影响

Effect of calcination temperature on photocatalytic properties of TiO_2 hollow microspheres

以分散聚合法制得的单分散阳离子聚苯乙烯(PS)微球为模板,钛酸丁酯为前驱体,采用溶胶-凝胶法在模板表面包覆TiO2壳层,并在不同煅烧温度下制备了晶相结构不同的微米级中空TiO2微球。采用TEM、SEM、FT-IR、XRD、UV-Vis DRS对样品的微观结构、相态组成及光催化性能进行了表征。结果表明TiO2中空微球平均粒径达到1.23μm,壳层厚度约为30nm;随着煅烧温度增加,锐钛矿晶粒尺寸会增加,并在700℃时出现混晶结构;在500℃煅烧得到的TiO2中空微球对甲基橙(MO)降解表现出比P25更好的光催化性能及光催化稳定性。

TiO2 hollow microspheres were successfully prepared with mono-dispersed cationic polystyrene microspheres as template,titanium tetrabutoxide as precursors by sol-gel method.TiO2 hollow microspheres with different crystalline phases were produced at different calcination temperatures.The microstructure,phase composition and photocatalytic activity of the as-synthesized products were characterized by using TEM,SEM,FT-IR,XRD and UV-Vis DRS.The experimental results indicate that the TiO2 hollow microspheres with the average diameters of 1.23μm possess a thin shell（30nm）.The crystallite dimension of anatase increases with the increasing of calcination temperature and appears mixed crystal structure at 700℃.The TiO2 hollow microspheres calcined at 500℃ exhibit better photocatalytic activity and stability for the decomposition of methyl orange（MO） in aqueous solution compare to P25.