Hexagonal CuCl Monolayer for Water Splitting: A DFT Study

In the past few years, enormous efforts have been put to develop earth-abundant semiconductor based photocatalysts for overall water splitting. In the present work, we predict a hexagonal CuCl monolayer (ML) to be promising for such semiconductor based photocatalytic reactions. Density functional theoretical (DFT) calculations have been employed to understand the overall water splitting reactions on the CuCl ML and CuCl bulk structure. The electronic structure, band edge alignment, and overpotential studies indicate that CuCl ML is a promising material for overall water-splitting reaction compared to the CuCl bulk structure. This is due to the stabilization of the valence band of the ML structure over the CuCl bulk structure.