Enhanced Performance of a Self‐Powered ZnO Photodetector by Coupling LSPR‐Inspired Pyro‐Phototronic Effect and Piezo‐Phototronic Effect

Abstract

AbstractUltraviolet detection is overriding priority in many military and civilian fields. A photodetector can be effectively enhanced by introducing piezo‐phototronic effect, pyro‐phototronic effect, and localized surface plasmon resonance (LSPR). Coupling piezo‐phototronic, pyro‐phototronic, and LSPR effect can be realized in a self‐powered photodetector based on ZnO/CuO nanorods covered with Au nanoparticles (NPs). The influences of LSPR, pyroelectric and external pressure on the performance of devices are thoroughly investigated, respectively. ZnO/CuO/Au devices display the most attractive performance under pressure of 73.7 N. The maxima of responsivity and detectivity are obtained as 0.81 mA W‐1 and 3.3 × 1013 Jones, respectively, under pressure of 73.7 N when detecting weak ultraviolet radiation (140 nW cm‐2). Responsivity and detectivity are dramatically enhanced by 17× and 12× compared to CuO/ZnO devices. Moreover, rise time and fall time reduce from 114/75 ms of a ZnO/CuO device to 18/12 ms of a ZnO/CuO/Au device under pressure of 64.7 N. These results demonstrate that LSPR, pyro‐phototronic, and piezo‐phototronic coupled effect makes greater improvement than the individual effects in the performance of photodetectors. This work probably can be a cornerstone of designing high‐performance photodetectors using other nanomaterial systems as well.