摘要
采用基于密度泛函理论(DFT)的第一性原理计算了Ce,S单掺杂及Ce/S共掺杂锐钛矿型二氧化钛(TiO_2)的能带结构、态密度和光学性质。结果表明:掺杂后晶格常数均变大,禁带宽度均减小,其中Ce/S共掺杂后由于S-3p电子轨道和Ce-4f电子轨道的共同作用引入了杂质能级,使得禁带宽度最小,吸收光谱发生红移;此外,Ce具有Ce^(4+)和Ce^(3+)两种可变价态,具有良好的电子迁移性质,阻止了电子和空穴之间的复合,预测了Ce/S共掺杂可提高TiO_2的光催化性能。
The energy band structure,density of electronic state and optical properties of Ce-doped anatase titanium dioxide（TiO_2）,S-doped anatase TiO_2 and Ce/S co-doped anatase TiO_2 are investigated with first-principles based on density functional theory（DFT）.The results show that the lattice constant is enlarged due to doping and the forbidden band is also decreased.For the Ce/S co-doped anatase TiO_2,its forbidden bandgap is the smallest of all because of the synergy of S-3p and Ce-4felectronic orbits,which leads to the red shifts of the absorption spectra.Furthermore,Ce atom has two kinds of variable valence（Ce^（4＋）and Ce^（3＋））,which can prevent the recombination of electrons and holes.The photocatalytic properties of TiO_2 can be improved by Ce/S co-doping.
出处
《激光与光电子学进展》
CSCD
北大核心
2016年第6期255-260,共6页
Laser & Optoelectronics Progress
基金
贵州省科技合作计划项目(黔科合LH字[2015]7744号)
贵州省普通高等学校创新人才团队(黔教合人才团队字[2012]06)
贵州省"125计划"重大科技专项项目(黔教合重大专项字[2014]037)
凯里学院青年课题(Z1123)
