Electronic structural properties of BiOF crystal and its oxygen vacancy from first-principles calculations

Abstract

First-principles calculations are performed to investigate the crystal and electronic structures of BiOF crystal and its oxygen vacancy BiO_7/8F. By analyzing the energy band structures, the total density of states and the partial densities of states, it is found that the band gaps for the perfect BiOF and BiO_7/8F are 3.12 and 2.65 eV, respectively, which are smaller than the experiment value of 3.64 eV. There is a new electronic state within the forbidden band in the BiO_7/8F, which could serve as a capture center for excited electrons, consequently improves the effective separation of electron-hole pairs, and makes the optical absorption band edge red shift. The calculated results demonstrate that the BiOF crystal and its oxygen vacancy BiO_7/8F could be the potential application as photocatalytic semiconductor materials.