采用基于密度泛函理论(DFF)框架下的第一性原理平面波赝势(PWPP)方法,模拟计算了纯的TiO2和Ce掺杂锐钛矿TiO2的能带结构、态密度及光学性质,分析了Ce掺杂对锐钛矿TiO2的晶体结构、能隙、态密度和光吸收系数的影响.结果表明:Ce掺杂锐钛矿TiO2晶体后,Ce的4f轨道进入导带使导带底向低能端移动,禁带宽度变小,吸收带红移,可见光区具有较大的光吸收系数,从而有助于提高TiO2的光催化活性,理论与实验基本吻合.
Using density function theory ( DFT), the band structure, electronic density states, optical properties of pure and Ce-doped anatase titanium dioxide ( Ce/TiO2 ) have been studied at plane wave ultra-soft pseudo-Potential (PWPP) in this paper. Subsequently, the influence of band structure, density of states, optical absorption coefficient by Ce-doped anatase titanium dioxide were studied. It shows that the 4f orbital of Ce inserts into the conduction band, which leads the shift of the bottom of the conduction band to lower enery zone and narrowing of band gap in Ce/TiO2. It may lead us to the conclusion that there should be a red shift of the absorption band and larger optical absorption coefficient to enhance the photocatalytic activity of TiO2 with the adulteration of Ce. The experimental phenomena also approve the result.