Sensitivity and selectivity Pt loaded SnO2–Co3O4 gas sensor for hydrogen detection

Here Pt loaded SnO2–Co3O4 composite was fabricated using a hydrothermal method and was applied to gas sensing for the first time. The structure, morphology, surface and gas sensing property of the sensing composites were respectively studied by XRD, SEM, HRTEM (Mapping), BET, XPS and electrochemical workstation. The gas sensing results showed that the response value of 1%Pt loaded SnO2/5%Co3O4 to hydrogen gas was 57.9, which was 9.6 times of pristine SnO2. And the response time of 1%Pt-loaded SnO2/5%Co3O4 to hydrogen was 12 s, which was much faster than that of pristine SnO2. The material also exhibited other excellent sensing performance such as selectivity for detecting H2 gas. Based on the experiments, the improved H2 sensing properties was due to synergistic effect of the spillover effect of Pt element and the formation of p-n junction. This work will provide valid method to fabricate SnO2-based gas sensing materials for real application to detect target gas.