Interfacial defect engineering and Photocatalysis Properties of hBN/MX2(M = Mo, W, and X = S, Se) Heterostructures

Abstract

Abstract Van der Waals (VDW) heterostructures have attracted significant research interest due to their tunable interfacial properties and potential in a wide range of applications such as electronics, optoelectronic, and heterocatalysis. In this work, the impact of interfacial defects on the electronic structures and photocatalytic properties of hBN/MX2(M = Mo, W, and X = S, Se) are studied using density functional theory calculations. The results reveal that the band alignment of hBN/MX2 can be adjusted by introducing vacancies and atomic doping. The type-I band alignment of the host structure was maintained in the heterostructure with n-type doping in the hBN sublayer. Interestingly, the band alignment changed to the type-II heterostructrue as VB defect and p-type doping was introduced in the hBN sublayer. This could be profitable for the separation of photo-generated electron−hole pairs at the interfaces and is highly desired for heterostructure photocatalysis. In addition, two Z-type heterostructures including hBN(BeB)/MoS2, hBN(BeB)/MoSe2, and hBN(VN)/MoSe2 were achieved, showing reducing band gap and ideal redox potential for water splitting. Our results reveal the possibility of engineering the interfacial and photocatalysis properties of hBN/MX2 heterostructures via interfacial defects.