Cu-I掺杂锐钛矿相TiO2的第一性原理研究  

First-principles Study on Cu-I Doped Anatase Phase TiO2

作　　者：宫长伟[1] 何新泽 陈峰华[1] 郭芬芳 侯泽宏 闫雪 GONG Changwei;HE Xinze;CHEN Fenghua;GUO Fenfang;HOU Zehong;YAN Xue(School of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China)

机构地区：[1]太原科技大学材料科学与工程学院,太原030024

出　　处：《人工晶体学报》2020年第3期505-510,共6页Journal of Synthetic Crystals

基　　金：山西省优秀科研人员科技创新计划(201805D211042);教育部材料各向异性与织构重点实验室基金(ATM20170003)。

摘　　要：采用基于密度泛函理论的第一性原理,计算了未掺杂,Cu、I单掺杂以及Cu-I共同掺杂锐钛矿相TiO2的电子结构和光学性质。结果表明,Cu、I单独掺杂TiO2都使得吸收带边红移,I单掺时I5p跟O2p态造成禁带宽度变小,吸收带边红移,Cu单掺时Cu的3d态杂质能级引入价带顶部造成禁带宽度变小,吸收带边红移更加明显。对于Cu-I共同掺杂TiO2,Cu主要作用于价带顶,I主要作用于导带底,进而引入杂质能级,使得禁带宽度明显减小,吸收带边明显红移,通过Cu-I协同作用形成电子、空穴俘获中心,有效地阻碍了电子-空穴对的复合,提高了对可见光的催化效率。The electronic structure and optical properties of undoped,Cu,I doped and Cu-I co-doped anatase phase TiO2 were calculated using the first-principles based on density functional theory.The results show that the red shift of absorption band edge can be caused by Cu,I doped TiO2 alone.For I doped TiO2,due to the interaction of the 5p orbital of I and the 2p orbital of O,the forbidden band width reduces,thus the absorption band edge is red shifted.For Cu doped TiO2,the 3d orbital of Cu introduces two impurity levels at the top of the valence band,which causes the top of the valence band to move upward.This makes the forbidden band width smaller,and the absorption band edge is significantly red-shifted.For Cu-I co-doped TiO2,Cu mainly acts at the valence band top,I mainly acts at the conduction band bottom,and then introduces impurity energy levels,so that the band gap is obviously reduced and the absorption band edge is sharply red shifted.The formation of electron and hole trapping centers by the synergistic action of Cu-I effectively hinders the recombination of electron-hole pairs and improves the catalytic efficiency for visible light.

关 键 词：第一性原理 TiO2 Cu-I掺杂 电子结构 光学性质 

分 类 号：O469[理学—凝聚态物理]