The monoclinic and tetragonal phases of bismuth vanadate (BiVO4) have been found to exhibit significantly different photocatalytic activities for water splitting. To assess a possible surface effect on the phase-dependent behavior, we calculate and compare the geometries and electronic structures of the monoclinic and tetragonal BiVO4 (001) surfaces using hybrid density functional theory. The relaxed atomic configurations of these two surfaces are found to be nearly identical, while an excess hole shows a relatively stronger tendency to localize at the surface than the bulk in both phases. Possible factors for the phase-dependent photocatalytic activity of BiVO4 are discussed.
Bibliographical noteFunding Information:
We would like to thank the R. A. Welch Foundation (F-1535) and the National Science Foundation (DMR-1122603) for financial support, and the Texas Advanced Computing Center for use of their computing resources. Helpful discussions with William A. Goddard III are also greatly acknowledged.