Fabrication of sheet-like ZnO/ZnS heterostructures with enhanced H2S sensing performance at low operation temperatures

Abstract

A sheet-like ZnO/ZnS-based sensor with a sensitive response and excellent selectivity to H2S at low operation temperatures was prepared using a hydrothermal method combined with a sulfuration process. Meanwhile, x-ray diffraction, x-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy measures were carried out to characterize the crystallographic information, elemental distribution, and microstructure of the sheet-like ZnO/ZnS. Results of the gas-sensing tests show that the response value of ZnO/ZnS-6 to 10 ppm of H2S reaches 90 at 100 °C, and the effective detection limit is as low as 1 ppm. The enhanced gas-sensing performance is attributed to the sheet-like microstructure and the formation of ZnO/ZnS heterojunctions. To H2S, the prepared ZnO/ZnS sensor shows satisfactory sensitivity, selectivity, and stability, and the lower heating temperature augurs wider potential applications.