Enhanced triethylamine sensing properties by designing Au@SnO2/ZnO nanosheets directly on alumina tubes

A triethylamine (TEA) sensor working temperature of 280 °C with high sensitivity and selectivity for TEA gas has been successfully fabricated by building Au@SnO2/ZnO nanosheets. By introducing a seed layer, ZnO nanosheets have been directly grown on Al2O3 tubes with a facile hydrothermal method. The Au@SnO2/ZnO structure is formed by utilizing DC-sputtering and pulsed laser deposition (PLD) methods. Compared with the pristine ZnO and SnO2/ZnO nanosheets sensors, the Au@SnO2/ZnO nanosheets sensors measured at 280 °C get a higher response of 48.1 toward 50 ppm of TEA gas. Moreover, the Au@SnO2/ZnO nanosheets sensor exhibits excellent selectivity. The enhanced sensing properties of the Au@SnO2/ZnO nanosheets sensor are discussed with a model of semiconductor depletion layer on the basis of n-n heterojunction and Schottky contact.