New Two-Dimensional WS₂/ZrSi₂N₄ Heterostructure as photocatalyst for Water Splitting into Hydrogen

Abstract Heterostructure construction is an important strategy for separating photogenerated electron-hole pairs and enhancing optical absorption ability of photocatalysts. In this work, we performed WS2/ZrSi2N4 heterostructure calculations about its structural and electronic properties based on the density functional theory. Our calculations show that BB2-stacking is most stable in all possible stacking configurations of WS2/ZrSi2N4 heterostructure. In addition, the charge transfer route of type-Z scheme is observed for the WS2/ZrSi2N4 heterostructure, which is beneficial for separating the electron-hole pairs and suppressing the carrier recombination. The stronger optical absorption ability of the WS2/ZrSi2N4 heterostructure is maintained compared with individual WS2 and ZrSi2N4 monolayers. These results suggest that the WS2/ZrSi2N4 heterostructure maybe is the potential for photocatalytic water splitting in hydrogen applications.