Self-powered graphene/4H-SiC nanowire array-based ultraviolet photodetectors with fast response time and low dark current for promising wireless ultraviolet communication

Abstract

Self-powered ultraviolet photodetectors (UV PDs) capable of detecting UV light signals without using an external power supply have become particularly attractive because of their high sensitivity, consistent optical response, ultra-small size, low energy consumption, and long-term robustness for the future. Here we reported a self-powered UV PDs coupling of two-dimensional (2D) single-layer graphene and one-dimensional (1D) 4H-SiC nanowire arrays. The fabricated PDs can feature an ultra-high on-off ratio of 6301 at 0 V and the 2D-1D architectural exhibits a low dark current of ∼4 pA, an ultra-fast response of 4.89 ms. The high performance was associated with the formed heterojunction between the 2D graphene and 1D 4H-SiC nanowire array and the high carrier mobility of the graphene. Moreover, the 2D-1D PDs with a large switching ratio and ultra-fast response time can be beneficial to achieve efficient, real-time, and accurate information transmission under 275 nm UV light, shedding some light on the development of high-performance wireless optical communication systems.