Ultrawide and Self-Powered PbS Quantum Dots/4H-SiC Nanopillar Array Heterojunction Photodetector and Its Application in the Light Power Density Recognition System

Broadband self-powered photodetectors have become the core devices of next-generation photovoltaic systems. However, a majority of conventional broadband self-powered photodetectors have deficiencies in aspects such as heterojunction integration methods and light capture capability. To solve these problems, a broadband self-powered photodetector based on a PbS quantum dot/4H-SiC nanopillar array heterojunction is proposed herein. The device enables detection from 200 to 1100 nm, with a responsivity and detectivity of 6.12 A/W and 3.02 × 10¹² Jones under 275 nm illumination, respectively (V_ds = 5 V). At V_ds = 0 V, the responsivity, detectivity, and fill factor of the device are 502 mA/W, 1.69 × 10¹² Jones, and 0.53 (λ = 275 nm), respectively. According to these characteristics, we integrated our device into a light power density recognition system and the device could recognize the light power density accurately. The results show that our device possesses promising potential for future photodetection applications.