Ab-initio insights into electronic structures, optical and photocatalytic properties of Janus WXY (X/Y = O, S, Se and Te)

Two-dimensional materials attracted widespread attention due to their striking performances compared with bulk materials. In this presentation, we theoretically investigate the electronic structures, optical and photocatalytic properties of Janus WXY (X/Y is O, S, Se and Te) through first-principles calculations. Our results indicate the recombination rate of photogenerated electron-hole pairs could be distinctly reduced because of the internal electric field of Janus WXY (X/Y is O, S, Se and Te) nanostructures. Moreover, Janus WXY (X/Y is S, Se and Te) own the decent band gaps and band-edge positions with water redox potential, i.e. the reduction and oxidation potentials are both contained by the corresponding band gap regions, demonstrating the significent potential as efficient photocatalysts for water splitting. The acid environment (pH = 0) can be used as the most suitable condition to forecast the significant potentical applcation for Janus WXY (X/Y is S, Se and Te) materials as distinguished photocatalysts for water splitting reactions. Addtionally, the response of the band gaps (EG) of Janus WXY (X/Y is S, Se and Te) systems to tensile strain strains is more sensitive than compressive strain. These findings are intended to provide appealing significance for the fascinating applications of Janus WXY (X/Y is S, Se and Te) in the field of water splitting and offer a reliable guidelines for experiments.