Electronic and optical properties of the PtSe2/boron phosphide van der Waals heterostructure

Based on the first-principles calculations, we investigate electronic and optical properties of PtSe2/boron phosphide (BP) van der Waals heterostructure (vdWH). The PtSe2/BP heterostructure displays type-I band alignment with a direct band gap of 0.846 eV. The electric field and biaxial strain allow the vdWH to achieve the band alignments of type-I and type-II. More importantly, the transition from semiconductor to metal is completed in the heterostructure under the applied electric field. Interestingly, the optical absorption of the PtSe2/BP heterostructure occurs to red shift with the positive electric field and blue shift with negative electric field or biaxial strain. In addition, the band alignment has a transition from type-I to type-II for the monolayer BP/fewlayer PtSe2 heterostructure. It is meaningful that the monolayer PtSe2/few-layer BP heterostructures maintain type-I band alignment. The results suggest that the PtSe2/BP heterostructure can be widely used in optoelectronic, photocatalytic and light-emitting applications in future research.