碳掺杂二氧化钛光催化性能的第一性原理研究

First-principles study on the photocatalysis in the C-doped TiO_2 rutile

使用第一性原理方法,计算了C掺杂TiO2材料的缺陷结构与能量,分析了在不同晶体生长环境下C掺杂TiO2晶体中的缺陷稳定性变化规律。结果表明在氧化条件下C掺杂TiO2中缺陷将主要以CTi的形式存在,而在还原气氛下得到的C掺杂TiO2中材料中缺陷结构主要以CO形式存在。对材料态密度的分析表明,CO缺陷结构能够在价带顶附近产生合适的能级,导致材料具有优秀的光催化性能。

First - principles calculations were carried out to investigate the energies and defect structures of C - doped TiO2 rutile. The effect of the crystal growing condition on the defect stabilities has been analyzed using the defect formation energies. Results show that the C substituting on an O site appears under reduction condition, and C substituting on a Ti site appears under the oxidation condition. The density of states calculations show the C substituting on an O site can provide the better photocatalysis performance.