Decorating spherical In2O3 nanoparticles onto ZnO nanosheets for outstanding gas-sensing performances

The presence and detection of hazardous environmental gases at deficient concentrations are essential to protect human beings from intensive gas exposures. Therefore, the development of high-response gas sensors is vital to overcome these overwhelming issues. The spherical In2O3 nanoparticles are successfully decorated onto ZnO nanosheets in ZnO@In2O3 (ZIO) nanocomposites via a simple co-precipitation method. The as-prepared nanocomposites are exposed to gas-sensing applications. The fabricated gas sensors exhibit high sensing response and selectivity towards NO2 gas than other gases, tested at various working temperatures and different range of gas concentrations. The gas-sensing property of ZnO nanosheets and ZIO nanocomposites has been investigated, which reveals that 10 wt% ZIO nanocomposites shows the outstanding response of 68 at 70 ppm (1.88% higher than pristine ZnO NSs), possesses fast response/recovery time (43, 65 s) respectively, and demonstrates excellent stability and repeatability. A plausible nanostructure formation and gas-sensing mechanism are also discussed in detail. The fabricated sensors are considered potential applicants in the development of the NO2-based gas sensor industry.