摘要
采用基于密度泛函理论的第一性原理平面波超软赝势方法研究了纯锐钛矿相TiO_2及Ce掺杂后的TiO_2晶体的能带结构、电子态密度和光学性质.计算结果表明,由于杂质Ce的掺入,使掺杂后的TiO_2的导带下方和费米能级附近形成杂质能级,成为光生电子的捕获中心,使导带底下移,使禁带宽度减小到1.72 e V,从而降低光生电子和空穴的复合几率,同时使光吸收带边发生红移,在可见光区的吸收系数增大,有效提升了光催化效率.掺杂后体系折射率变小,光透性增强.由此我们可以在TiO_2中掺杂特定元素以提高光催化效率,制作出符合特定条件的光学元件.
The electronic band structure, density of state and optical properties of anatase TiO2 and Ce-doped TiO2 were studied by using the plane-wave ultrasoft pesudopotentials method based on density functional theory. The calculated results show that Some news enemy impurity levels appear at the bottom of the conduction band and near Fermi level of Ce doped TiO2. Conduction band moves down and width of band gap decreases to 1.72 eV, it becomes the light electronic capture center, and reducing light electrons and holes of composite risk, which leads to increase in coefficient of visible absorption simultaneously, thereby facilitating the enhancement of the photocatalytic efficiency. After doping, the refractive index decreases, which leads to the enhanced light permeability. Thus we can dope specific elements to in order to improve the photocatalytic efficiency of TiO2 and produce in accordance with specific conditions of optical element.
出处
《伊犁师范学院学报（自然科学版）》
2016年第4期35-40,共6页
Journal of Yili Normal University：Natural Science Edition
基金
2016年伊犁师范学院一般项目
关键词
锐钛矿TIO2
稀土掺杂
第一性原理
电子结构
光学性质
anatase TiO2
Rare earth doped
the first-principle
electronic structure
optical property
