LSPR-Enhanced Pyro-Phototronic Effect for UV Detection with an Ag-ZnO Schottky Junction Device

Sensitive and rapid detection of low-power density ultraviolet (UV) light is of great significance for various applications such as space exploration, biological analysis, environmental sensors, communications, and imaging. However, the persistent photoconductivity (PPC) of photodetectors, which are based on ZnO, will cause a long decay time and make it difficult to capture weak light signals. In this work, the pyro-phototronic effect of ZnO is integrated with the localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) to enhance the performance of ZnO-based photodetectors. The self-powered photodetector is consisted of the ZnO nanowires (ZnO NWs) and Ag NPs, which can detect 325 nm UV light with a power density of 340 nW cm(-2) quickly and sensitively. Compared with the photodetector without Ag NPs, the performance is significantly improved. Under the 325 nm UV light with the same power density, the best responsivity, and detectivity are 8.82 x 10(-5) A W-1 and 4.9 x 10(10) Jones, respectively. And the fast response time is remarkably reduced to 8.72 ms. These results help to understand the performance of LSPR enhanced photodetectors deeply and expand the methods for preparing high-performance photodetectors.