Preparation of Ag-loaded mesoporous WO3 and its enhanced NO2 sensing performance

Abstract

Ordered mesoporous WO3 and Ag-loaded mesoporous WO3 have been synthesized by using three-dimensional cubic KIT-6 as a hard template. A series of material characterization methods were employed to characterize the as-synthesized materials above and gas sensing properties were measured. It showed that the as-obtained ordered mesoporous structure materials have excellent crystallite and the pore sizes were about 9nm which matched with the result of BET results. Furthermore, the NO2 sensing properties of the sensors based on mesoporous WO3 and different molar ratios of Ag-loaded (0.2%, 0.5% and 1.0%) mesoporous WO3 were detected by utilizing a static test system, respectively. The sensor using 0.5% Ag-loaded mesoporous WO3 exhibited much higher response, shorter response and recovery time and excellent selectivity to NO2 comparing with the sensors those based on other Ag-loaded ratio mesoporous WO3 and the pure mesoporous WO3.