Preparation of silver nanoparticles modified SnO2 humidity sensor for tobacco storage environment detection

In this paper, silver nanoparticles (AgNPs) modified SnO 2 (Ag/SnO 2 ) nanocomposite with excellent humidity performance was prepared by hydrothermal method. Experimental results demonstrate that AgNPs enhance the performance of the SnO 2 humidity sensor, which is primarily attributed to increase the oxygen vacancies on the surface of the SnO 2 through the incorporation of AgNPs. Density functional theory (DFT) demonstrated that more oxygen vacancies can enhance the chemical and physical adsorption energy of water molecules by SnO 2 , and decompose more water molecules into conductive H + ions: simultaneously, the response/recovery times and hysteresis error of SnO 2 are reduced. Compared to the SnO 2 humidity sensor, Ag/SnO 2 exhibits low humidity hysteresis (2.7%), relatively short response/recovery time (5/8 s) and high sensitivity (24292.3). Furthermore, the Ag/SnO 2 humidity sensor employed in this study has successfully demonstrated its efficacy in detecting humidity levels within tobacco storage environments, which expands the potential applications of humidity sensors.