Effect of perovskite electrode composition on mixed potential sensor response

In this article, the influence of perovskite electrode composition on an electrochemical based mixed potential sensor response is reported. Specifically, various stoichiometry of Strontium doped Lanthanum Chromite materials were used as the sensing electrode. Yttria-Stabilized Zirconia was used as the solid electrolyte and Pt as the counter electrode. The effect of varying doping levels of Strontium on the sensor response was studied. NO, NO2, C3H6, and C4H10 were used as test gases. The sensor response was studied under open-circuit and current biased conditions.Based on sensitivity and selectivity evaluations, the device configuration ‘La0.9Sr0.1CrO3/YSZ/Pt’ was found to behave as a selective total hydrocarbon sensor at 500 °C when operated under open-circuit conditions. On the other hand, ‘La0.7Sr0.3CrO3/YSZ/Pt’ exhibited minimal cross-sensitivity to hydrocarbons facilitating its use as a selective NOx sensor when operated under a current bias. The variation in the sensor response and selectivity for different electrode materials indicate that it might be possible to develop multi-electrode sensor platform for identifying a suite of analytes with improved selectivity and sensitivity.