A type-II two-dimensional Blue-P/Al2SO van der Waals heterostructure with the potential for photovoltaics and photocatalysis applications

The enhancement of photocatalytic efficiency in monolayer materials receives a substantial boost through the deliberate construction of two-dimensional van der Waals heterostructures. In this work, we introduce a novel two-dimensional Blue-P/Al2SO vdW heterostructure through rigorous first principles calculations. Blue-P/Al2SO forms a type-II heterostructure with an indirect band gap of 1.64 eV (PBE) and 2.35 eV (HSE), and exhibits a large relative ratio (D), which arises from the effective separation of photogenerated electron-hole pairs and preventing their recombination. We have confirmed its dynamic and thermal stability by analyzing the phonon spectrum and conducting ab-initio molecular dynamics simulations at room temperature. The interface generates a built-in electric field that expedites the reorganization of photo-generated holes within Blue-P monolayer and photo-generated electrons within Al2SO monolayer. Crucially, the band edges of this heterostructure covers the water redox potential in a wide range of pH from acidic to basic solution, this provides a positive outlook for experiments aimed at preparing it as a photocatalyst. Furthermore, our investigations reveal that the light-absorption ability of the Blue-P/Al2SO vdW heterostructure is relatively strong. The highest light absorption peak is 3 x 10(5) cm(-1) at 600 nm wavelength. Consequently, this newly designed Blue-P/Al2SO vdW heterostructure exhibits significant potential for applications in solar energy conversion and serves as a promising photocatalyst for facilitating the process of water splitting.