A high performance self-driven photodetector based on a graphene/InSe/MoS2 vertical heterostructure

Hybrid van der Waals heterostructures comprising ultrathin layers of different materials and offering the possibility of novel properties and unusual charge transport characteristics have become a reality in recent years. Here, we vertically stack graphene, a transition metal dichalcogenide and a III-VI semiconductor together and report a novel self-driven photodetector based on a graphene/InSe/MoS2 heterostructure. The device shows rectifying and bipolar behavior. In the self-driven mode it exhibits high photoresponsivity (110 mA W-1), fast photo-response (less than 1 ms) and high detectivity (over 10(10) Jones). It also shows ambient operational stability over one month of operation and nearly uniform photocurrent distribution because of the efficient electron-hole pair separation arising from the large built-in potential at the interface of MoS2 and InSe. Our graphene/InSe/MoS2 heterostructure holds promise for novel self-driven optoelectronics based on III-VI/transition metal dichalcogenide heterojunctions.