An Advanced Robust van der Waals Heterostructure Photodetector with Ultralow Dark Current and a Large Linear Dynamic...

The diversity of 2D materials and their excellent optoelectronic properties have brought revolutionary opportunities and challenges for novel multifunctional semiconductor devices. As a representative multielement van der Waals semiconductor, AgInP₂S₆ offers a new platform for developing novel optoelectronic devices but suffers from bottlenecks including low response speed, narrow response spectrum, and single-functionality. Herein, an advanced robust ReSe₂/AgInP₂S₆ vdWs heterostructure photodetector with a response spectrum spanning from the ultraviolet to near-infrared region was successfully constructed, enabling polarization-sensitive imaging and optical communication. An ultralow dark current (∼10^-14 A), self-driven detection capability, large linear dynamic range (72.0 dB at 525 nm and 40.3 dB at 980 nm), long-term stable photoswitching operation, and fast response speed (rise/decay times: 170/150 μs) were achieved, facilitated by the efficient separation of photogenerated carriers within the built-in electric field at the heterointerface, as confirmed by high-spatial-resolution photocurrent mappings. Additionally, the heterostructure exhibits polarization-sensitive photodetection with dichroic ratios of 2.58 and 3.30 at 980 nm under self-powered and external bias-driven modes, respectively. This work establishes a novel strategy for developing high-performance, multifunctional photodetectors, enabling new design and application avenues for next-generation, advanced optoelectronic devices.