Self-Powered Broadband UV-NIR Photodetectors Based on InSe/PtS2 Van der Waals Heterostructure

Van der Waals heterostructures (vdWHs) consisting of 2D materials offer a practical and effective approach for engineering multifunctional, high-performance photodetectors. However, 2D vdWHs photodetectors based on photoconductive effects require an external power input and are often accompanied by a large dark current, which hinders the development of miniaturization and portability of devices and greatly limits the application of devices in complex environments. Herein, a self-powered photodetector constructed from an InSe/PtS2 vdWH with an extremely low dark current (approximate to 10(-14) A) at zero bias and a large rectification ratio of 5.1 x 10(3) is reported. Leveraging the robust built-in electric field of the InSe/PtS2 vdWH, the device demonstrates pronounced photovoltaic effects, characterized by an open-circuit voltage of 0.395 V and a substantial short-circuit current of 37.1 nA. Remarkably, a high responsivity and detectivity of 211 mA W-1 and 8.58 x 10(12) Jones, an excellent light on/off ratio of 0.8 x 10(7) , and a fast response time of 465/470 mu s are achieved, at zero bias. The device showcases a broadband self-powered photoresponse spanning from 265 to 1064 nm. This study demonstrates the high potential of the InSe/PtS2 vdWH for broadband self-powered photodetector applications.