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. (C) 2000 Elsevier Science S.A. All rights reserved.