High-performance near-infrared Schottky-photodetector based graphene/InS van der Waals heterostructures.

Two-dimensional (2D) β-InS is a natural defective n-type semiconductor attracting considerable interest for its excellent photoelectronic performance. However, β-InS based photodetectors exhibited a weak near-infrared photoresponse compared to visible wavelength in past reports. In this work, high-quality 2D β-InS nanosheets were prepared by a space-confined chemical vapor deposition (CVD) method. Graphene/InS van der Waals heterostructures were constructed to realize an enhanced near-infrared photodetection performance by a series of transfer processes. The photodetectors based on graphene/InS van der Waals heterostructures through junction carrier separation exhibited a better infrared performance of high photoresponsivity ( ) of 0.49 mA W, external quantum efficiency (EQE) of 0.07%, and detectivity (*) of 3.05 × 10 jones using an 808 nm laser.