Electrical Conductivity and Sensitive Characteristics of Ag-Added BaTiO_3-CuO Mixed Oxide for CO_2 Gas Sensing

Carbon dioxide gas sensors based on BaTiO3-CuO composite with different concentrations of Ag addition (1, 1.5 and 2 wt%) have been prepared by stander ceramic method and sintered at 500 and 700°C for 5 h. Electrical conductivity and gas sensing properties of the prepared samples were investigated. Electrical conductivity measurement was used to characterize the obtained sintered sensor pellets. It was found that electrical conductivity and the sensitivity to CO2 were improved with Ag addition and sintering. The correlation between Ag content at different sintering temperature and sensing characteristics towards CO2 is discussed.