A self-powered MXene/InGaN van der Waals heterojunction mini-photodetector for visible light communication

Abstract

A van der Waals heterojunction-based photodetector has attracted significant interest due to its potential for high-speed visible light communication (VLC) application. Herein, we report a self-powered and high-performance MXene/InGaN van der Waals heterojunction visible light mini-photodetector (mini-PD). The combination of MXene and InGaN creates a Schottky junction that effectively separates the photoinduced electron/hole pairs, resulting in a robust heterojunction structure while enhancing carrier mobility and lifetime. The mini-PD exhibits the responsivity of 6.0 A/W, a specific detection rate of 9 × 1011 Jones, and rise/decay times of 7.1/183.2 μs under 470 nm blue light (36.5 μW/cm2) without bias voltage. The results show that MXene forms a robust type-II band arrangement with InGaN, which converts the optical signal into a large electrical signal and improves the stability of the mini-PD. This work provides a strategy for high-speed VLC without external energy input that has great potential for applications such as energy-efficient communication, sensor networks, and low-sensitivity detection.