Ag-decorated ZnO nanorods prepared by photochemical deposition and their high selectivity to ethanol using conducting oxide electrodes

Abstract

A novel gas sensor structure is presented in this work. It consists of LaNiO₃ thin film electrodes and gas sensitive Ag nanoparticle-decorated ZnO nanorods. ZnO nanorods were successfully synthesized by a facile wet chemical method in aqueous solution at 95 °C, and then the ZnO nanorods were decorated with Ag NPs through photochemical deposition. Dielectrophoresis was used to position the Ag-decorated ZnO nanorods on the LaNiO₃ electrodes. The as-prepared devices combined the advantages of one-dimensional nanostructure, highly ordered array, the chemical stability of the electrode and Ag decoration, which resulted in a dramatic sensing performance for gas detection. The as-prepared gas sensors have high selectivity to ethanol, as well as improved response and recovery speeds.