Self-Powered and Reconfigurable Double-Terminal MoS₂ Photodetector for Image Recognition

Two-dimensional (2D) semiconductors hold significant potential for the fabrication of self-powered reconfigurable devices due to their atomically thin body thickness and excellent heterogeneous integration capabilities. Despite these advantages, regulating polarity in 2D semiconductors remains challenging, and their complex heterostructures hinder practical applications. Here, we demonstrate a metal-semiconductor-metal (MSM) two-terminal structure to achieve self-powered and multiple reconfigurable functions in MoS₂ devices. By applying different voltage pulses to modulate the sulfur vacancy concentration, the device obtains a reversible internal electric field, leading to the bidirectional self-powered photocurrent that switches from negative to positive. This device achieves a fastest response speed of 224 μs and a maximum responsivity of 280 mA/W. Besides, we proposed a resistance-dependent method to achieve stable and reversible responsivity modulation and successfully implement the image processing and object detection using a convolutional neural network (CNN). This work provides a straightforward approach for integrating next-generation optoelectronic devices.