NH3 sensing performance of Pt-doped WO3•0.33H2O microshuttles induced from scheelite leaching solution

WO3 center dot 0.33H(2)O microshuttles (WMSs) self-assembled by numerous nanorods along the same direction were prepared based on a cheap tungsten-containing metallurgical raw material by combination processes of NaOH leaching and one-step hydrothermal method. The microstructures and gas sensing properties of various concentrations (0, 0.7, 1.0, and 1.3 mol%) of Pt-doped WMSs were investigated to improve their performance. The microstructural characterizations demonstrated that the WMSs assembled by one-dimensional WO3 center dot 0.33H(2)O nanorods were approximately 0.8-1.9 mu m in diameter. Such nanorods exhibited a single hexagonal structure with their diameters ranging from 17 to 62 nm. The gas sensing properties indicated that Pt-doped WMSs showed superior gas sensing performance in terms of the sensor response and NH3 selectivity in the operating temperature range of 25-225 degrees C as compared with pure one, and simultaneously Pt doping could significantly reduce the detection limit of NH3. Especially, 1.0 mol% Pt-doped WMSs exhibited the highest response of 28.2-1000 ppm NH3 at 175 degrees C, which was 4 times higher than pure one at 50 degrees C, indicating that it is a potential candidate material for the detection of NH3 gas.

Automated summary

WO3•0.33H2O microshuttles self-assembled by nanorods showed improved gas sensing properties with Pt doping, exhibiting enhanced sensor response and NH3 selectivity compared to pure WMSs. The Pt-doped WMSs, especially with 1.0 mol% Pt, demonstrated superior performance in detecting NH3 gas at various concentrations and temperatures, indicating their potential for gas detection applications.