Room temperature NO2 sensing properties of ZnO1-α coating prepared by hydrogen reduction method

NO 2 emission is currently one of the important factors threatening the quality of life of residents. Preparing ZnO-based gas sensors to monitor the concentration of NO 2 has attracted growing attention. This article reports a method for preparing ZnO 1-α by hydrogen heat treatment. The ZnO coating prepared by the spin coating method is directly placed in a reduced atmosphere with 3% hydrogen for heat treatment to produce a self-doped ZnO 1-α coating with oxygen vacancies , which can effectively narrow the bandgap. The article studied the influence of heat treatment time and visible light wavelength on sensing properties. The results show that under the conditions of room temperature and blue light irradiation, the coating heat-treated in a reduced atmosphere for 1 h showed the best gas-sensing properties to 1 ppm NO 2 with a response of 7.0. The outstanding selectivity of ZnO 1-α coating has been displayed.