Carbon-assisted synthesis of mesoporous SnO2 nanomaterial as highly sensitive ethanol gas sensor

Mesoporous SnO2 nanomaterials with the central pore sizes of 4.1 nm, 6.1 nm and 8.0 nm have been fabricated by a novel carbon-assisted synthesis method (CAS). By using this method, the pore size can be easily regulated by adjusting the concentration of glucose in the precursor solution. The prepared SnO2 nanomaterials with distinct pore sizes were characterized by transmission electron microscopy (TEM and HRTEM) and nitrogen adsorption–desorption analysis. Besides, the gas sensing properties of these mesoporous SnO2 nanomaterials were evaluated. Testing results reveal that the three kinds of mesoporous SnO2 nanomaterials exhibit short response/recovery time to ethanol gas and the ultralow detection limits of 100 ppb, 50 ppb and 400 ppb, respectively. The proper networked mesoporous nanostructure (NMNs) is responsible for the distinct response–recovery behavior and the mechanism to get the ultralow detection limit. The excellent gas sensing characteristic together with large-scale production and low-cost route hold a great promise for the application of ethanol detection at ultra-low concentration.