Ce掺杂与O空位对锐钛矿相TiO2磁学和光学性能影响的第一性原理研究  

First-principles Study on the Magnetic and Optical Properties of Ce Doped Anatase TiO2 with O Vacancy

作　　者：李聪[1] 付斯年[1] 郑友进[1] 吴春雷[1] LI Cong;FU Si-nian;ZHENG You-jin;WU Chun-lei(Heilongjiang Laboratory of New Carbon-base Functional and Superhard Material,Department of Physics,Mudanjiang Normal University,Mudanjiang 157011,China)

机构地区：[1]牡丹江师范学院物理系黑龙江省新型碳基功能与超硬材料重点实验室

出　　处：《人工晶体学报》2019年第8期1451-1456,共6页Journal of Synthetic Crystals

基　　金：黑龙江省教育厅项目(1353MSYYB016,1351MSYYB001,1352MSYYB001)

摘　　要：基于第一性原理计算,建立了含有不同Ce与O空位配比的锐钛矿TiO2模型。对各个体系的稳定性、磁性、电子结构及吸收光谱进行了计算。结果表明:Ce与近邻O空位间的自旋电子交换是锐钛矿TiO2净磁矩的来源,因此体系的磁性与Ce和O空位的相对位置有关。Ce或O空位浓度增加在费米能级附近形成的施主能级使得带隙宽度进一步减小,因此体系对可见光的吸收系数进一步增加。与局域性更强的Ce-4f电子相比,Ti-3d电子更易受激参与光催化反应,因此Ce掺杂引起的O空位及其浓度是影响锐钛矿TiO2光催化性能的主要因素。Base on first-principles, the anatase TiO 2 models with different ratio of Ce to O vacancy were established. The stability, magnetism, electronic structure and the absorption spectrum of all anatase models were calculated. Results show that the spin-electron exchange between Ce and the adjacent O vacancy is the source of the net magnetic moment of anatase TiO 2, so the magnetism of the system is related to the relative positions of Ce and O vacancies. The donor band near the Fermi level induced by increased Ce or O vacancy could reduce the band gap, so that the absorption coefficient of visible light of anatase is further increased. Compared with the localized Ce-4f electron, Ti-3d electrons induced by O vacancy are more susceptible to photocatalytic reactions, therefore, the O vacancy and its concentration caused by Ce doping are the main factors affecting the photocatalytic performance of anatase TiO 2.

关 键 词：Ce掺杂TiO2 第一性原理 O空位 电子结构 

分 类 号：O481.1[理学—固体物理]