Al-N共掺杂金红石相TiO_2的第一性原理研究

本文采用了基于密度泛函理论的第一性原理平面波超软赝势法对金红石相TiO_2进行了计算,其中内容包括未掺杂与单掺杂Al、单掺杂N以及共掺杂Al-N这四种不同情况下TiO_2的能带结构与态密度和光吸收系数的研究.计算结果表明:单掺杂Al和N时,均不同程度地改变了其能带结构,光吸收能力均有提高但效果不佳.在共掺杂Al-N时,TiO_2晶格常数产生了改变,并出现了新的杂质能级.由于杂质能级存在于TiO_2禁带范围内,减小了电子跃迁至导带所需能量,从而提高了其光吸收能力,其效果相对于单掺杂来说更有明显提高.

First-principles study on rutile TiO2 co-doped with aluminum and nitrogen

Abstract: In this paper, the first-principles plane wave super-soft pseudopotential method based on density functional theory is used to calculate rutile TiO2. Which includes the pure TiO2 and single-doped Al, single-doped N and co-doped Al-N four different conditions of the band structure and density of TiO2 and the density of light absorption coefficient of the study. The calculated results show that the ability of light absorption is improved by the addition of Al and N, but the effect is not good. When the Al-N is co-doped, the lattice constant of TiO2 is changed and a new impurity level appears. Since the impurity energy level exists in the band gap of TiO2, the energy required for electron transition to conduction band is reduced, Thereby increasing its light absorption capacity, the effect relative to the single doping is more obvious improvement.