Electronic and photocatalytic performance of boron phosphide-blue phosphorene vdW heterostructures

Hydrogen generation via photocatalytic water splitting is considered as a source of clean energy and an alternative approach to deal with energy crises and environmental problems. By using first-principles computations, we determine that boron phosphide-blue phosphorene van der Waals heterostructure is a potential candidate for overall water splitting at low pH values (0–3). The heterostructure is a semiconductor with a direct band gap of 1.47 eV and possesses type-II band alignment. More importantly, this heterostructure contents the water reduction and oxidation levels for water splitting, with enhanced optical absorption in infrared, visible and ultraviolet regions. Particularly, tensile strain can enhance the optical absorption in the visible range and increase the solar energy conversion efficiency. Our study widens the application of boron phosphide-blue phosphorene heterostructures, and helps design more heterostructured photocatalysts.