摘要
In this work, a high-performance room temperature NO 2 chemoresistive gas sensor is fabricated using a MoS 2 /ZnO nanohybrid. The nanohybrid is synthesized by drop-casting liquid exfoliated MoS 2 nanosheets on ZnO nanorods. The uniform network-like distribution of MoS 2 nanosheets on the nanorods is confirmed by various characterization techniques. Under UV-activation, the nanohybrid sensor exhibits remarkable responses of 91% and 2310% at 5 and 500 ppb NO 2 , respectively. In addition, full recovery to the base resistance is observed in each sensing cycle. The low concentration sensitivity is 0.135 ppb −1 and the lowest detection limit is estimated to be around 0.2 ppb. These two values are superior when compared with other reports. The adsorption/desorption kinetics has been studied in detail using the Langmuir adsorption model. The saturated response, the adsorption, and the desorption constant are determined to be 2744%, 3.52 × 10 –5 ppb −1 s −1 , and 3.50 × 10 –3 s −1 , respectively. The outstanding performance of the sensor can be attributed to the synergetic effects of MoS 2 and ZnO including creation of abundant adsorption sites and fast charge carrier migration.