Ti掺杂SnO2 半导体固溶体的第一性原理研究

Ti掺杂SnO2固溶体是钛基氧化物耐酸阳极的重要组成部分. 采用基于密度泛函理论的第一性原理对Sn1-xTixO2(x=0, 1/12, 1/8, 1/6, 1/4, 1/2, 3/4, 5/6)固溶体的电子结构进行计算, 分析了能带结构、 电子态密度和电荷密度以及晶格参数的变化. 结果表明, Ti掺入SnO2晶格后, 其晶格参数随组分增加近似呈直线降低, Ti-O键的共价性强于Sn-O键. 掺杂后带隙仍为直接带隙, 且随着掺杂比例的增加, 带隙逐渐减小. 当掺杂比例x=0.5时, 形成能达到最低值(-6.11 eV), 固溶体最稳定. 本文的计算结果为钛基氧化物电极材料的研究与开发提供了一定的理论依据.

First-principles Study of Ti-doped SnO2 Semiconductor Solid Solutions

Ti doping SnO 2 solid solution is an important part of titanium based oxide proof-acid anode.Electronic structures of Sn 1-xTi xO 2 solid solutions（x=0,1/12,1/8,1/6,1/4,1/2,3/4,5/6） were investigated by first-principles calculations based on the density functional theory.The energy band structures,density of states and Mulliken charge population were analyzed.The results show that the corresponding lattice parameters reduce linearly with composition,Ti-O bond covalent nature is stronger than that of Sn-O bond,band gap is still direct band gap after doping,and the band gap gradually decreases with the increase of doping ratio. The Sn₀.5Ti₀.5O₂ solid solution has the highest stability because of its minimum formation energy value of-6.11 eV.These results provide a theoretical basis for the study and development of titanium based oxide electrode materials.