H2S gas sensing enhancement of Au-decorated SnO2 nanospheres synthesized using hydrothermal and microwave methods

In this study, non-oriented Au-decorated SnO2 nanospheres (NSs) were synthesized using hydrothermal and microwave methods. The SnO2 spheres ranged from hundreds of nanometers to a microscale. The oxygen vacancy on the surface increased after Au adsorption on the surface of the SnO2 NSs, ultimately showing a synergistic effect with the spillover effect of the existing Au catalyst. Specifically, at 100 degrees C and 200 degrees C, the response to 10 ppm H2S gas improved to 16.14 and 46.81, respectively. These gas sensing effects were approached individually by being divided into two disadvantages (oxygen adsorption and homojunction) and five advantages (oxygen vacancies, spill-over, surface area, H2S + SnO2 reaction, and H2S + O-2 reaction). Based on this reference, we investigated SnO2 NSs of various sizes and functions by adjusting the process variables.