Highly sensitive sensor based on ordered porous ZnO nanosheets for ethanol detecting application

摘要

Ethanol sensors with high sensitivity are demanded for healthcare and environmental monitoring applications, especially in drunk driving detection. In this work, we present a high-performance gas sensor based on ordered porous ZnO (PZnO) nanosheets with a low cost. Gas sensing tests show that PZnO exhibits the highest ethanol sensing responsiveness at 307 °C to some toxic organic volatiles. The response of our PZnO based sensor is 212.0 toward 200 ppm ethanol vapor, the response and recovery time are only 8 s and 7 s, respectively. Compared with other ZnO based sensors shown in recent literatures, our PZnO based sensor exhibits faster response/recovery speed and higher sensitivity, which can be ascribed to the single-crystalline feature, more (002) facets exposure, ordered porous structure and a large amount of oxygen vacancy on the sensitive surface according to the sensing mechanism and density functional theory simulation study. The response also shows good linear relationship with the ethanol concentration in logarithm. Besides, the PZnO sensor is immune to high relative humidity. These characteristics enable PZnO based sensors for ethanol detecting applications.