Density functional theory study of the structural, electronic, and surface reaction properties of bismuth vanady1 oxyhalide BiVO3F

TL;DR

This study uses density functional theory to analyze BiVO3F, revealing its electronic structure, surface properties, and potential for solar energy applications, highlighting its stability and catalytic activity for water oxidation.

Contribution

First comprehensive DFT analysis of BiVO3F's structural, electronic, and surface reaction properties, guiding future photocatalyst design.

Findings

BiVO3F is a direct band gap semiconductor with a band gap matching experiments using hybrid functionals.

The (001) surface is the most stable and exposes V and Bi sites as active sites.

High overpotential for OER due to difficulty in O-O bond formation on surface.

Abstract

BiVO3F is a promising material used in solar energy conversion systems. Here, we first report the calculated structural, electronic, and surface reaction properties using PBE and hybrid density functionals. We found it is a direct band gap semiconductor, and the calculated band gap is consistent with experimental value only using the hybrid density functional with a fraction of Hartree Fock (HF) exchange {\alpha}=0.1. The (001) surface is the most stable surface among all the low index (001), (010), and (100) surfaces. There are V and Bi sites exposed on (001) surface which can serves as activity sites. That is quite different from BiVO4 where only Bi sties can be taken as surface reaction sites. The OER intermediates OH* and OOH* prefer to form a bridge structure on both V and Bi sites. This makes the first proton removal step is very easy, but the O-O bond is difficult to form which leads the overpotential of OER is very high. Our work plays a guide principle to design the high efficiency photocatalysis and photoanodes based on BiVO3F.