Self-Powered Photoelectrochemical Photodetectors Based on Electrochemically Exfoliated In2Se3 Nanosheets

Two-dimensional (2D) In2Se3 has received considerable attention due to its suitable band gap, good photoresponse, and high stability, making it a good candidate for high-performance photodetectors. Self-powered 2D In2Se3-based photodetectors consisting of heterojunctions usually require a complex fabrication process, hindering their application. In this work, we synthesize 2D In2Se3 nanosheets by an electrochemical exfoliation method and fabricate self-powered In2Se3 photoelectrochemical (PEC) photodetectors by a simple drop-casting method. The self-powered In2Se3 PEC photodetectors show a broadband photoresponse from ultraviolet (365 nm) to near-infrared (850 nm) with a high responsivity of 1.88 mA/W, fast response speed of 1 ms, and good stability, surpassing most 2D material-based PEC photodetectors. Our results demonstrate that self-powered In2Se3 PEC photodetectors hold great promise in next-generation high-performance optoelectronic devices.