Water adsorption at the (010) and (101) surfaces of CuWO4

Abstract

Copper tungstate (CuWO₄) has attracted significant attention over the past two decades. However, the adsorption of water onto CuWO₄, which plays a critical role in the photocatalytic water splitting process, has not been investigated in detail. In this study, we have employed density functional theory (DFT) calculations to investigate water adsorption onto the CuWO₄ pristine (010) and reduced (101) surfaces. Surface phase diagrams as a function of temperature and partial pressure of H₂O were also constructed to determine water coverage under particular environmental conditions. Our study provides a comprehensive understanding of the adsorption of water on the major CuWO₄ surfaces, which is an important preliminary step in our investigation of photocatalytic water splitting over CuWO₄.