Ultrasensitive NO2 gas sensor based on Sb-doped SnO2 covered ZnO nano-heterojunction

Sb-doped SnO2 covered ZnO nano-heterojunction (Sb-doped SnO2/ZnO NHs) are prepared by using a microwave hydrothermal method. The effect about morphology and gas sensor performance of the SnO2/ZnO NHs with Sb-doping is studied in detail. The SEM indicated that the morphology of SnO2 changed from nanowires to nanosheets by Sb-doping and the growth direction of SnO2 was vertical to the plane of ZnO from the TEM. Compared with undoped SnO2/ZnO NHs, the gas sensor response became higher as the concentration of Sb-doping increased which shows the sensor performance can be enhanced by Sb-doped SnO2. The change of morphology by Sb-doping increased the number of surface active sites and defects. In addition, a certain concentration of O vacancy was induced by Sb-doping to provide more free electrons that can also be captured by NO2. The research may provide a reference for studying the effect of Sb-doped composite materials and gas sensor performance.

Automated summary

Sb-doped SnO2/ZnO nano-heterojunctions were prepared using a microwave hydrothermal method, and the effects of Sb-doping on the morphology and gas sensor performance of SnO2/ZnO NHs were studied in detail. The study found that Sb-doping changed the morphology of SnO2 and enhanced the gas sensor response.