Study of WO3-based sensing materials for NH3 and NO detection

Gas sensing materials of WO3 loaded with 1 wt.% metal oxides were prepared and applied for NH3 and NO detection. The measurement of NH3 and NO sensing properties of the materials revealed that WO3+1 wt.% Mg, WO3+1 wt.% Zn, WO3+1 wt.% Mo and WO3+1 wt.% Re characterized good responses to NH3 and NO. As a whole, these materials have low resistance, high sensitivity and fast response to NH3 and NO compared with pure WO3. The possibility of NH3–NO equivalent point sensor was discussed. It can be used for real time monitoring, and controlling the reduction of NO using NH3.