钆、镉共掺纳米TiO_2光催化剂的合成及其光催化性能研究

Synthesis of Gd-Cd Co-Doped Nano TiO_2 Photocatalyst and Its Photocatalytic Activity

以钛酸四正丁酯、硝酸钆和硝酸镉为原料,采用溶胶-凝胶法合成了Gd和Cd共掺杂型纳米TiO2光催化剂,借助X-射线粉末衍射(XRD)、X-射线光电子能谱(XPS)及UV-vis等测试手段对样品进行了表征,并以罗丹明B为模型污染物考察了掺杂量对样品光催化活性的影响规律。XRD分析表明,所得粉体均为锐钛矿相纳米TiO2,且Gd和Cd共掺后随着掺杂量的增加,纳米TiO2特征衍射峰宽化,强度降低;UV-vis光谱分析表明,适量钆(0.2%)掺杂使得催化剂在400～600nm的可见光区域对光响应,而在Gd掺杂的基础上掺杂Cd后,催化剂在紫外光区及400～600nm的可见光区吸收显著增强,对光具有更高的利用率;光催化实验表明,钆和镉掺杂对纳米TiO2光催化活性有显著的影响,当钆和镉掺杂量为0.2%、0.3%时其光催化活性最好。

Using tetrabutyltitanate,gadolinium nitrate and cadmium nitrate as raw materials,Gd-Cd co-doped nanometer TiO2 have been successfully synthesized by a sol-gel process,and characterized by XRD,XPS and UV-vis techniques.Rhodamine B was chosen as model pollutant to evaluate photocatalyst＇s activity.The XRD analysis result indicated that the as-synthesized samples were all anatase nanometer TiO2.UV-vis absorption spectrum indicated after Gd-Cd co-doping TiO2 had strongger absorption in UV region,and had obvious response to visible light.Photocatlytic expenriment results showed when the gadolinium and cadmium doping quantity approximately was 0.2%and 0.3%respctively,nanometer TiO 2 had the better activity.