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采用溶胶-凝胶法制备了纯TiO2和La掺杂TiO2复合纳米粉体,通过XRD,UV-Vis等测试手段分析了在紫外光照射下,以降解甲基橙为探针反应研究其可见光催化性能。结果显示样品均为锐钛矿相纳米TiO2,稀土元素镧掺杂后纳米TiO2特征衍射峰宽化,强度降低;掺入的La主要以La2O3的形式存在,同时有一部分形成Ti-O-La键;La掺杂可减小TiO2晶粒尺寸及增大催化剂比表面积;与未掺杂的二氧化钛相比较,适当含量的镧掺杂可有效促进TiO2表面光生载流子的分离,从而显著提高其光催化活性。当La/Ti的摩尔比为0.010时,可见光催化性能最好。
Pure TiO2 and La-doped TiO2 nanocomposite powders were prepared by sol-gel method. The photocatalytic properties of pure TiO2 and La-doped TiO2 nanocomposites were investigated by XRD and UV-Vis measurements under ultraviolet light with methyl orange as the probe reaction. The results show that the samples are anatase phase nano-TiO2. After lanthanum is doped by rare earth element, the characteristic diffraction peaks of nano-TiO2 are broadened and the intensity is decreased. La is mainly present in the form of La2O3, and part of Ti-O-La bonds ; La doping can reduce the grain size of TiO2 and increase the specific surface area of the catalyst; compared with undoped titanium dioxide, proper content of lanthanum doping can effectively promote the separation of photocarriers on the surface of TiO2 and thus significantly increase its light Catalytic activity. When the molar ratio of La / Ti is 0.010, the photocatalytic performance is the best.