N-Cu共掺杂金红石相TiO_2光催化剂的第一性原理研究  

First-Principles Study on Rutile TiO_2 Photocatalyst Co-doped with N and Cu

作　　者：张菊花[1,2] 冯庆[1,2] 朱洪强[1,2] 杨英[1,2] 

机构地区：[1]重庆师范大学物理与电子工程学院,重庆401331 [2]重庆市光电功能材料重点实验室,重庆401331

出　　处：《中国激光》2015年第6期192-200,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(61106129;61274128);重庆市自然科学基金(cstc2013jcyj A50021;cstc2014jcyj A50015);重庆市教委科学技术研究项目(KJ1400524)

摘　　要：TiO2是一种广泛应用的无机金属氧化物半导体材料,利用掺入杂质来改善TiO2的光催化和光电转换性能已成为近年来研究的热点。采用密度泛函理论体系下第一性原理的平面波超软赝势方法研究了单N掺杂、单Cu掺杂和N-Cu共掺杂金红石相TiO2的电子结构和光学性质。结果表明:N与Cu共掺杂后,由于N2p电子与Cu3d电子协同作用,在TiO2禁带中产生了新的杂质能级。其中一条处于稳态,另一条处于亚稳态,电子跃迁能有效减小,更有利于光生电子-空穴对有效分离,大大改善了TiO2的光催化性能。N与Cu共掺杂使TiO2的光吸收系数曲线在可见光区发生了比单N掺杂和单Cu掺杂更大的红移,反射率也增大。TiO2, a kind of inorganic metal oxide semiconductor material, has been widely utilized. It is becoming a research hotspot to improve photocatalytic activity and photoelectric conversion property of TiO2 through incorporation of impurities. The electronic structure and optical properties of N doped, Cu doped and N-Cu co-doped rutile TiO2 are studied by using plane wave pseudopotential method of first-principles based on density functional theory. The results show that with N and Cu co-doped TiO2, new impurity energy levels would be formed in band gap of TiO2 due to the synergistic effect of 2p electrons of N and 3d electrons of Cu. Among them, one of impurity levels is in steady-state, the another level is in metastable state. It is favorable for decreasing the transition energy of electron and effective separation of photoproduced electrons-hole pairs, which largely improve the photocatalytic activity of TiO2. The curve of optical absorption coefficient of N-Cu co-doped TiO2 has larger red shift in the visible region than that of N doped TiO2 and Cu doped TiO2, and the reflectivity of N-Cu co-doped TiO2 also increases.

关 键 词：材料 金红石相TiO2 N—Cu共掺杂 第一性原理 电子结构 光学性质 

分 类 号：O482.3[理学—固体物理]