UV Light and H₂ Gas Dual Sensing Properties of ZnO/InGaZnO Match-Head Nanorods

Abstract

In this study, ZnO/InGaZnO (IGZO) match-head nanorods (NRs) were fabricated for light/gas dual sensors. A match-head IGZO structure was successfully grown on ZnO NRs. Scanning electron microscope and transmission electron microscope images reveal that amorphous IGZO capsule-like heads were sputtered on the top of crystallized ZnO NRs. Results of X-ray photoelectron spectroscopy spectra indicate that oxygen defects can be generated by the growth of IGZO. Additionally, hydrogen sensing and UV light detection measurements were performed on NRs under various IGZO growth conditions. Results indicate that incorporation of an IGZO match-head on a ZnO NR can functionally enhance hydrogen gas sensing and UV light detection capabilities owing to the increase of trapping states, free carriers, electric fields and surface areas exposed to gas and light. Due to their compact size, steady response and simple fabrication, ZnO/IGZO-based hydrogen gas and UV light dual sensors devices are promising for future environmental monitoring.