Highly sensitive ethanol gas sensor based on CeO2/ZnO binary heterojunction composite

Abstract In this work, ZnO nanosheets composited with CeO2 were successfully synthesized through a facile hydrothermal method combination with wet impregnation method. Various methods were employed to characterize the microstructure of the as-prepared products. The results demonstrated that the morphology of the CeO2/ZnO products have uniform nanosheets structure. In addition, gas sensing tests demonstrated that compared with pure ZnO, the sensor based on 7 at% CeO2/ZnO nanosheets exhibited obviously enhanced sensing properties toward ethanol. The response value was 90 toward 100 ppm ethanol, which was almost five times higher than that of pure ZnO. The excellent sensing performance can be ascribed to the n-n heterojunction between ZnO and CeO2.