Highly sensitive and selective acetone gas sensors based on modified ZnO nanomaterials

In this work, Fe-doped ZnO (Fe–ZnO) porous nanosheets gas sensors were fabricated to detect acetone gas. The pure and 0.5, 1, 3 mol% Fe–ZnO nanosheets were synthesized through a hydrothermal method. The crystalline structure, morphology, and composition were identified by XRD, SEM, TEM, BET, and XPS. At the optimal working temperature of 365 °C, the 0.5% Fe–ZnO sensor to 100 ppm acetone gas can reach the maximum response of 105.7, which is 3.68 times higher than that of the pure ZnO device. Meanwhile, it also shows a response of 2.3 at the low detecting limit of 1 ppm, indicating its good response at low gas concentrations. The sensor exhibits well repeatability and selectivity. The improvement in gas-sensitive performance is related to the reduction in the bandgap and the increase in oxygen vacancies of the material after doping. All experimental results show that Fe–ZnO porous flake particles have excellent potential for fabricating efficient acetone sensing materials.