N,Cr共掺锐钛矿TiO_2电子结构和光学性质的第一性原理研究  

First-principle study on the electronic structures and optical properties of( N,Cr) co-doped anatase TiO_2

作　　者：孙凌涛[1] 郭朝中[1] 伏春平[1] 石东平[1] 

机构地区：[1]重庆文理学院新材料技术研究院,重庆402160

出　　处：《功能材料》2015年第23期23075-23079,共5页Journal of Functional Materials

基　　金：重庆市自然科学基金资助项目(cstc2014jcyj A50038;cstc2012jj A50036);重庆市教委科学技术研究资助项目(KJ1501118);重庆市永川区科委资助项目(Ycstc;2014nc4002);重庆市高校微纳米材料工程与技术重点实验室开放课题资助项目(KFJJ1404)

摘　　要：采用第一性原理的平面波赝势方法研究了N、Cr单一掺杂及共掺杂锐钛矿TiO_2的能带结构、态密度和光学性质。结果表明,N单一掺杂体系中N2p杂质轨道交叠在费米能级上;Cr单一掺杂体系中杂质能级主要由O2p和Cr3d轨道杂化贡献;N、Cr共掺杂致使导带及价带相对费米能级明显下降,同时在原禁带基础上形成了新的杂质能级、禁带宽度减小,锐钛矿TiO_2的光吸收带红移,其吸收系数增大、能量损失缩小,有效增强了锐钛矿TiO_2的光催化效率。In this work,the band structure,density of states and optical property of N or Cr-doped and N + Cr co-doped Ti O2 anatase were studied by the plane-wave ultrasoft pseudopotential method based on the first-principle density functional theory. The results shows that the N2 p orbital overlaps with the Fermi level in single N-doping system and the impurity level of single Cr-doping system is mainly contributed by the hybridization of O2p and Cr3 d orbitals. The co-doping of N and Cr has led to an important decreasing of the conduction band and the valence band in contrast with Fermi level,has formed an impurity level and reduced the forbidden band width on the basis of the original band. Besides,the optical absorption of the TiO_2 anatase red-shifts with the increase of absorption coefficient and the reduction of energy loss,which largely enhances the photo-catalysis efficiency of TiO_2

关 键 词：锐钛矿TIO2 N+Cr共掺杂 电子结构 光学性质 

分 类 号：O436.2[机械工程—光学工程] O469[理学—光学]