High-performance, self-powered UV photodetector based on Au nanoparticles decorated ZnO/CuI heterostructure

Self-powered Ultraviolet (UV) photodetectors (PDs) have attracted great attention due to their outstanding performance. Herein, we report the successful fabrication of self-powered UV PDs based on ZnO/CuI/Au heterojunction . An ultra-high on/off ratio of 4250 and fast rise/decay times of 0.41/0.08 s have been demonstrated from the ZnO/CuI/Au PD. Moreover, the PD exhibits a high responsivity of 61.5 mA/W and detectivity of 1.7 × 10 10 Jones. The device displays long-term cyclic stability with 98.9% retention after 1000 cycles continuous test and superior environmental stability with 97.1% retention tested after 6 months. The synergistic effects of plasmonic Au nanoparticles and ZnO/CuI pn heterostructure play important roles in the enhancement of the photodetect ability. The concept of employing plasmonic Au nanoparticles onto the heterostructure indicates huge potential in achieving self-powered UV PDs for practical applications.