First-principles study on the optical spectrum of N/P doped TiO2-anatase

Abstract

In this paper, the geometry structure, electronic structure and optical properties of TiO2-anatase, TiO2-anatase doped with N and TiO2-anatase doped with N/P atoms were investigated by the plane-wave ultrasoft pseudopotential method based on the first-principles density functional theory. It demonstrates that there exist additional states in the band gap as TiO2-anatase was doped with N and TiO2-anatase was doped with N/P atoms, and the band gap narrows. The conduction band and valence band position of TiO2-anatase doped with N/P move to lower energy levels, that enhance the ability of oxidation and reduction, which is conducive to improve the photocatalytic performance. Red shift phenomenon, oxygen vacancies increase and enhanced photocatalytic properties of TiO2-anatase doped with N/P has been found by XRD, IR, RRS optical spectrum of the N/P doped TiO2- anatase, which verify our theory analysis.