(010) surface and interface for water-splitting applications*

Bismuth vanadate (BiVO₄) is a promising photoanode for water splitting that is frequently paired with an oxygen evolution catalyst (OEC). However, little is known about interfacial properties of BiVO₄ with water or with the OEC. In our earlier work [1], we showed that the photoelectrochemical performance of BiVO₄ is greatly impacted by its surface termination. We present our recent findings from an integrated experimental and computational effort aimed at an atomistic understanding of the BiVO₄ (010) interface with water and with the OEC for different surface terminations. We combined first-principles calculations using Quantum Espresso (https://www.quantum-espresso.org/) and Qbox (http://qboxcode.org/) with XPS and resonant PES in ambient conditions to probe how the presence of water influences charge localization. We identify structural moieties with adsorbed water that can explain the observed enhancement in the polaron signal. Finally, we discuss how surface termination impacts the interfacial properties with water based on ab-initio molecular dynamics simulations.

[1] D. Lee, W. Wang, C, Zhou, X. Tong, M. Liu, G. Galli, K.-S. Choi. “The impact of surface composition on the interfacial energetics and photoelectrochemical properties of BiVO4 .” Nature Energy. 6, 287 (2021).