Feasibility of potentiometric oxygen gas sensor based on perovskite and sodium titanate measuring electrode

A new solid potentiometric sensor for the oxygen gas detection using NASICON as solid electrolyte is proposed and tested in the range 300–700 °C for a feasibility study. The measuring electrode is a mixture of Na2Ti3O7–Na2Ti6O13 and La1−xSrxMnO3±δ (LSM) as mixed electronic and ionic conductors. A system based on Ni-NiO/Na2Ti3O7–Na2Ti6O13 is used as solid internal reference. A linear relationship was observed between the sensor output and the logarithm of oxygen concentration. The response is in good agreement with the theoretical Nernstian equation in a large range (10−2 to 10−16 atm). A very fast response was observed.