CO sensing properties of SnO2–CeO2mixed oxides

A series of SnO2–CeO2powder mixed oxides (with 5, 10, and 20 % wt SnO2) was prepared, characterized and used to study the sensing properties for CO, in absence of oxygen, using a CO-helium mixture. The results have shown that the SnO2–CeO2powder has good response and recovery characteristics. This powder has better sensitivity to CO than pure SnO2at the working temperature of 400–450 °C. A sensing mechanism was proposed and discussed in this paper. The results have indicated that the SnO2–CeO2mixed oxides can be used as CO sensors, in absence of oxygen.