Preparation of Zr-doped CaTiO_3 with enhanced charge separation efficiency and photocatalytic activity

具有高电荷分离效率和光催化活性的锆掺杂钛酸钙的制备（英文）

A series of Zr-doped CaTiO3 powders were prepared with the mild co-precipitation method and calcined at 850℃ for 3 h. The as-prepared Zr-doped CaTiO3 samples were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, UV-Vis diffuse reflectance spectra （DRS） and X-ray photoelectron spectra （XPS）. XRD result revealed the presence of single perovskite phase of CaTiO3. UV-Vis diffusive reflection spectra of Zr-doped CaTiO3 indicated that the absorbance obviously increased in the visible light irradiation. XPS analysis showed that two types of oxygen existed on the photocatalyst surface, including lattice oxygen and absorbed oxygen. Their photocatalytic activity in the case of the degradation of methyl orange in water and photoelectrochemical activity were also tested. The 5%Zr-doped （mole fraction） CaTiO3 sample showed the highest photocatalytic activity. The enhanced photocatalytic activity was ascribed to the change of the lattice structure, existence of oxygen vacancies and increase of the photogenerated charge separation efficiency.

通过温和共沉淀方法合成一系列锆掺杂的钛酸钙,并在850°C下焙烧3 h。采用扫描电镜(SEM)、X射线衍射(XRD)、紫外-可见漫反射光谱(DRS)和X射线光电子能谱(XPS)等手段对合成的锆掺杂的钛酸钙进行表征。XRD结果表明,锆掺杂钛酸钙以单一的钙钛矿相存在;紫外-可见漫反射光谱分析表明,锆掺杂钛酸钙在可见光区的吸收明显增强;XPS分析显示,在光催化剂表面存在2种类型的氧,即晶格氧和吸附氧。此外,对其光催化降解甲基橙的性能以及光电化学性能进行测试。结果表明,5%Zr(摩尔分数)掺杂钛酸钙具有最高光催化活性。晶格结构的改变、氧空穴的存在、光生电荷分离效率的提高都有利于提高锆掺杂的钛酸钙的光催化活性。