Ultrasensitive Solar-blind Ultraviolet Photodetector Based on FePSe3/MoS2 Heterostructure Response to 10.6 mu m

Metal phosphorous tri-chalcogenides are a category of new ternary 2D layered materials with a wide range of tuneable bandgaps (1.2-3.5 eV). These wide-bandgap semiconductors exhibit great potential applications in solar-blind ultraviolet (SBUV) photodetection. However, these 2D solar-blind photodetectors suffer from low photoresponsivity, slow photoresponse speed, and narrow operation spectral region, thereby limiting their practical applications. Here, an ultra-broadband photodetection based on a FePSe3/MoS2 heterostructure with coverage ranging from solar-blind ultraviolet 265 nm to longwave infrared (LWIR) 10.6 mu m is reported. Notably, the device exhibits excellent weak light detection capability. A high photoresponsivity of 33 600 A W-1 and an external quantum efficiency of 1.57 x 10(7)% are demonstrated. A noise-equivalent power as low as 5.7 x 10(-16) W Hz(-1/2) and a specific detectivity up to 1.51 x 10(13) cm Hz(1/2) W-1 are realized in the SBUV region. The room temperature LWIR photoresponsivity of 0.12 A W-1 is realized. This work opens a route to design high-performance SBUV photodetectors and wide spectral photoresponse applications.