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利用基于密度泛函理论的第一性原理计算了Mo单掺杂和Mo/S共掺杂锐钛矿相TiO2的能带结构、电子分态密度、电子密度和吸收光谱。结果表明,Mo单掺杂在锐钛矿相TiO2导带底下方引入了两条主要由Mo 4d轨道组成的掺杂能级,而Mo/S共掺杂在TiO2的禁带之内共引入了四条掺杂能级,位于价带顶上方的两条主要由S 3p轨道组成,而位于导带底下方的两条掺杂能级则主要由Mo 4d和S 3p轨道杂化形成。Mo单掺杂和Mo/S共掺杂分别使TiO2的禁带宽度增大0.36 eV和0.43 eV,从而出现吸收带边的蓝移。电子密度图表明,Mo单掺杂对TiO2的晶格影响较小,但Mo/S共掺杂则使TiO2的晶格畸变程度加大。
The band structure, electronic configuration density, electron density and absorption spectrum of Mo single-doped and Mo / S co-doped anatase TiO2 have been calculated using the first-principle based on density functional theory. The results show that Mo single doping introduces two doping levels mainly composed of Mo 4d orbitals under the conduction band of anatase TiO2, and Mo / S co-doping is introduced into the forbidden band of TiO2 Four doping levels, two at the top of the valence band are mainly composed of S 3p orbitals, and two doping levels at the bottom of the conduction band are mainly formed by the hybridization of Mo 4d and S 3p orbital. Mo single doping and Mo / S co-doping increase the bandgap of TiO2 by 0.36 eV and 0.43 eV respectively, resulting in a blue shift of the absorption band edge. The electron density map shows that Mo single doping has little effect on the lattice of TiO2, but the Mo / S co-doping increases the degree of lattice distortion of TiO2.