真空热处理对纳米TiO<sub>2-x</sub>可见光催化的影响

真空热处理对纳米TiO_2-x可见光催化的影响

摘要: 本文以TiCl4水解法制备的锐钛矿型纳米TiO₂为原料,采用真空热处理对其进行改性处理。利用XRD、XPS、紫外可见分光光度计等测试手段对真空热处理前后的纳米TiO₂粉末进行了表征,并对结果进行了分析。结果表明,纳米TiO₂经400℃×40min,真空度在1.0E-2Pa以下热处理后,在TiO₂晶格中形成了氧空位缺陷,改变了TiO₂的能带结构,得到了具有可见光催化活性的TiO_2-x。其吸收阀值红移至550nm左右,实现了其对可见光的吸收。

Abstract: Anatase nano-TiO₂ prepared by hydrolyzing TiCl₄ solution was modified by vacuum heat treatment.XRD,XPS,and UV spectrophotometer were used to characterize the phase structure and light properties of both TiO₂（before treatment） and TiO₂-x（after treatment）.The results showed that oxygen vacancy in the lattice of TiO₂ was formed after it was modified at 400℃ for 40min under vacuum below 1.0E-2Pa.The band structure of TiO₂ was also changed after vacuum heat treatment.The TiO_2-x photocatalyst with visible-light sensitivity and activity was obtained in present study.The optical absorption edge of this photocatalyst was significantly extended to about 550nm,which is in the visible light range.