煅烧温度对TiO_2粉体的微观结构及光催化特性的影响

Influence of Calcination Temperature on Microstructure and Photocatalysis Properties of TiO_2 Powders

以钛酸丁酯为原料,采用溶胶-凝胶法制备TiO2粉体。利用X射线衍射谱、拉曼光谱、红外光谱、扫描电子显微镜和紫外-可见光分光光度计分别研究煅烧温度对TiO2粉体的微观结构、颗粒形貌与紫外光光催化性能的影响。实验结果表明:随着煅烧温度的升高,TiO2粉体发生了锐钛矿到金红石结构的相变,相变温度大约在623K^673K,且等轴状颗粒的尺寸逐渐增加。同时发现锐钛矿结构的TiO2粉体对甲基橙的紫外光光催化活性最高,而无定形及金红石结构不利于粉体的紫外光光催化活性。

By using tetrabutyl titanate as source precursor, TiO2 powders were prepared by Sol-gel method. The influence of calcination temperature on the microstructure, morphology and photocatalysis properties of TiOz powers were investigated by means of X-ray diffraction, Laman spectra, FTIR spectra, scanning electron microscopy （SEM） and ultraviolet radiation-visible （UV-vis） spectrophotometer, respectively. The results showed that TiO2 powers had a phase transitions from anatase to rutile with increasing cal.eination temperature. The phase transition temperature was about 623 K--673 K. Meanwhile, all the powder particles displayed equidimensional shape and the particle size increased with the increment of calcination temperature. In addition, anatase TiO2 powders had the highest ultraviolet photocatalysis properties on degradation of methyl orange while both amorphous and rutile TiO2 powders were bad on ultraviolet photocatalysis properties.