Use of NASICON/Na2CO3 system for measuring CO2

The detection of CO2 gas at several temperatures using NASICON as a solid electrolyte interacting with Na2CO3 or Na2CO3–BaCO3 mixtures has been demonstrated previously. Further work has shown that although the detection of CO2 is possible, with a pseudo-Nernstian response, the values of the slope and the constant in the emf versus logPCO2 equation were not always the same as those expected by the theory. The results also suggest that the presence of oxygen in the gas mixture may affect the response of the sensor. Other effects, as the decomposition of Na2CO3 and the formation of Na2O in the surface of NASICON should also be considered.