Enhanced hydrogen gas sensing through the utilization of a hybrid nanostructure combining ZnO nanotubes and HiPIMS Cu3N thin film

Abstract

Hydrogen (H2), a renewable energy source, has emerged as a promising and clean fuel alternative to conventional fossil fuels. It has garnered significant attention from researchers due to its wide-ranging applications in promoting sustainable growth. However, accurately detecting atmospheric H2 levels becomes crucial due to its flammability. This study introduces a room temperature-based hydrogen gas sensor composed of vertically hydrothermally grown ZnO nanotubes (ZNTs) with or without the incorporation of a Cu3N thin film, creating a hybrid nanostructure. The ZNTs and ZNTs/Cu3N nanohybrid samples were fabricated with multi-finger configurations of Palladium (Pd) interdigitated electrodes. The ZNTs/Cu3N nanohybrid exhibited exceptional sensing capabilities compared to those of the as-prepared ZNTs. It was tested with varying concentrations of H2, ranging from 10 to 500 ppm, at room temperature. The ZNTs/Cu3N nanohybrid's superior performance is due to its larger surface area, enabling improved gas ion adsorption, increased oxygen vacancies, and more surface-active sites compared to ZNTs alone. The Cu3N layer beneath the ZNTs greatly impacts the gas sensor's performance by lowering the ZNTs/Cu3N nanohybrid's band gap (1.85 eV), enhancing its H2 detection capabilities. The ZNTs/Cu3N nanohybrid demonstrates great potential for future gas sensor applications, offering valuable insights for advanced sensing technology development.