(1. 河北大学 电子信息工程学院，保定 071002；
2. 河北大学 计算材料研究中心，保定 071002)
摘 要: 利用基于密度泛函理论的第一性原理平面波超软赝势方法对未掺杂、Fe和S单掺杂及Fe-S共掺杂锐钛矿相TiO2的电子结构进行计算，分析Fe、S单掺杂及Fe-S共掺杂对锐钛矿相TiO2的晶体结构、能带、态密度和光吸收性质的影响。结果表明，掺杂后TiO2的晶格发生畸变，原子间键长的变化使晶格发生膨胀；掺杂后TiO2的禁带宽度减小，并在禁带中引入杂质能级，导致TiO2的吸收带边红移；与Fe和S单掺杂相比，Fe-S共掺杂锐钛矿相TiO2的吸收带边红移程度更大。
关键字: TiO2；Fe-S共掺杂；密度泛函理论；晶体结构；红移
（1. College of Electronic and Informational Engineering, Hebei University, Baoding 071002, China;
2. Research Center for Computational Materials，Hebei University, Baoding 071002, China）
Abstract:The electronic structures of Fe-doped, S-doped and Fe-S co-doped anatase TiO2 were calculated by the first-principles plane wave ultra-soft pseudo-potential method based on the density functional theory (DFT). The effects of doping on crystal structures, energy bands, density of states (DOS) and optical properties were analyzed. The results show that, after doping the lattices of TiO2 are distorted by the doping and the bond length change of atoms leads to the lattice expansion. The impurity levels in the band gap and the decrease of the forbidden band width lead to the red-shift of absorption band edge in anatase TiO2. Fe-S co-doped anatase TiO2 shows a stronger red-shift in the absorption band edge than the single Fe-doped and single S doped samples in the optical spectra.
Key words: TiO2; Fe-S co-doping; density functional theory; crystal structure; red-shift
