Theoretical study on the hydrogen evolution performance of two-dimensional Z-scheme AlN/ReS2 heterojunction photocatalysts

AlN and ReS2 monolayers are the foundation for constructing the unique 2D vdW heterojunction. Based on density functional theory, the photocatalytic performance of AlN/ReS2 heterojunction was systematically studied using first-principles calculation methods. According to the calculation findings, the AlN/ReS2 heterojunction possesses a band gap of 1.79 eV, and the staggered band structure efficiently divides the holes and electrons produced by photo-generated light. The Z-scheme charge transfer mechanism is achieved via the AlN/ReS2 heterojunction, allowing the recombination of electron-hole pairs within the heterojunction. In the AlN layer for reduction processes, this mechanism leaves highly reducing photo-generated electrons, whereas in the ReS2 layer for oxidation reactions, it leaves highly oxidizing photo-generated holes. The AlN/ReS2 heterojunction's band edge location also spans the pH = 1 to 7 water oxidation-reduction potential. The AlN/ReS2 heterojunction exhibits good light absorption capabilities and charge carrier mobility. As a result, for applications involving water splitting, the AlN/ReS2 heterojunction is a promising photocatalyst.