碳掺杂锐钛矿TiO_(2)的结构和电子性质  

Structures and Electronic Properties of Carbon-doped Anatase Titania

作　　者：郎秀峰 薛佳卉 王唯锦 LANG Xiufeng;XUE Jiahui;WANG Weijin(Material Simulation and Computing Laboratory,Department of Physics,Hebei Normal University of Science&Technology,Qinghuangdao Hebei,066004;School of Medical Engineering Integration,Beijing Institute of Technology,China)

机构地区：[1]河北科技师范学院物理系材料模拟与计算研究室,河北秦皇岛066004 [2]北京理工大学医工融合学院

出　　处：《河北科技师范学院学报》2021年第3期24-29,共6页Journal of Hebei Normal University of Science & Technology

基　　金：国家自然科学基金项目(项目编号:21303006);河北省自然科学基金项目(项目编号:B2017407009);河北科技师范学院博士启动基金项目。

摘　　要：运用第一性原理计算系统研究了两类C掺杂(C取代O和C填隙)锐钛矿TiO_(2)的结构和电子性质。结果表明,通过优化可以得到3种C取代O掺杂结构和8种C填隙掺杂结构。C取代O的结构中存在C—Ti键,而C填隙的结构碳以CO和CO^(2-)_(3)的形式存在。基于这些优化结构,计算的态密度证实以C原子或C的二聚体的形式取替O未改变纯TiO_(2)的带隙,而其它掺杂结构都明显地加大了TiO_(2)的带隙。C取代O掺杂的TiO_(2)带隙几乎无变化,而其它形式掺杂的TiO_(2)带隙明显加宽了。此外,这些掺杂结构的带隙中都存在杂质能级,有利于可见光的吸收。Structures and electronic properties of the anatase TiO_(2)are studied with two kinds of Carbon dopant(C substituted O and C filled gap)by using first-principles calculations.The results show that three substitutional C-doped TiO_(2)structures and eight interstitial C-doped TiO_(2)structures were optimized.There are three C-Ti bonds in the substitional C-doped structures,and CO or CO_(3)groups appear in the interstitial C-doped structures.Based on these optimized structures,the calculated density of states show that the doped structure with a C atom or a C dimer exhibits similar band gap with respect to the pure TiO_(2),while other doped structures own wider band gap.In addition,there are impurity energy levels in the band gaps of all doped structures,which is beneficial to the absorption of visible light.

关 键 词：碳掺杂 TiO_(2) 态密度 杂质能级 

分 类 号：O469[理学—凝聚态物理]