A self-powered dual-functional hybrid Cu2O/SiNWs heterojunction with applications in broadband photodetectors and ozone gas sensors

Abstract

Dual-functional sensors can replace two or more individual sensors in a platform so they decrease the system area. However, these devices have a major limitation in that they feature high power consumption. A self -powered dual-functional device that detects broadband light detecting and senses ozone (O3) is reported. The device architecture features a solution-processed Cu2O thin film that covers silicon nanowire (SiNW) arrays to form a heterojunction. The hybrid Cu2O/SiNWs heterojunction structure allows light trapping and gas adsorption because it has a large specific interface area. The proposed device generates an open-circuit voltage of 0.36 V when illuminated using visible-light and can be used to detect various concentrations of O3 with excellent selectivity and long-term stability. This Cu2O/SiNW heterojunction structure shows that capability to develop self-powered dual-functional sensors in the future.