Bias‐Tunable Dual‐Functional Broadband Optoelectronic Synaptic Devices for Neuromorphic Visual and Brain‐Like Intelligence Applications

Dual‐functional optoelectronic devices capable of integrating photodetection and photosynaptic functionalities are increasingly desirable for next‐generation neuromorphic visual systems and brain‐like intelligence. Here, a bias‐tunable dual‐functional optoelectronic device based on lead‐free perovskite/organic semiconductors heterojunction is developed with broadband photoresponses covering the ultraviolet to near‐infrared region. The synergistic heterojunction and defect‐mediated charge trapping and release dynamics allow the device to switch between photodetection and photosynaptic modes by the applied bias. Under self‐powered condition, the device functions as a stable photodetector with excellent long‐term operational endurance and reliable performance in photoplethysmography sensing. Under an external bias of −0.8 V, the device can emulate key synaptic behaviors under optical stimulation across a broadband spectrum from ultraviolet to near‐infrared. Furthermore, when the photosynaptic characteristics of the device are incorporated into a reservoir computing system, an image recognition accuracy exceeding 90% can be achieved, demonstrating its promising application in artificial visual neural networks. This work provides a novel strategy for designing dual‐functional optoelectronic devices with broadband responses, bias‐dependent operation, advancing intelligent perception systems and brain‐like intelligence that integrate optical sensing and neural information processing.