Zr/Nb掺杂锐钛矿型TiO_2第一性原理分析

First Principle Analysis of Zr/Nb Doped Anatase TiO_2

采用第一性原理的平面波超软赝势方法,分析了纯锐钛矿TiO2及Zr、Nb单掺杂和共掺杂锐钛矿TiO2等四种晶体模型的电子结构和光学性质。研究发现,掺杂对TiO2的电子结构带来了影响;Zr 4d杂质态与价带杂化叠加,Nb 4d杂质态发生能级分裂,对能带带来较大影响;Zr掺杂TiO2的吸收带边出现轻微红移,Nb掺杂和Zr-Nb共掺杂TiO2发生轻微蓝移。

The electronic structure and optical property of anatase TiO2,doped with Zr and Nb,were studied by First principle analysis,based on ultrasoft pseudopotential plane wave method.It was showed that the electronic structure of TiO2 was modified due to doping.The impurity states of Zr 4d were located at the bottom of the valence bands.The Nb 4d impurity states were splitted in the TiO2 octahedron,which made band gap wider.A red shift of the absorption edge was found in Zr-doped TiO2,while blue shift of the absorption edge was found in Nb-doped and Zr-Nb codped TiO2.