Electrical characterization of a mixed potential propylene sensor

In this article, electrical characterization of a ‘La0.8Sr0.2CrO3/YSZ/Pt’ non-Nernstian propylene gas sensor is reported. The effect of the concentration of the test gas (25–200 ppm) on the sensor response was studied using impedance spectroscopy and current–voltage curves. For a fixed operating temperature of 510° C, the interfacial resistance was seen to decrease with increase in the analyte concentration. A 48% reduction in interfacial resistance has been observed when switched from air to 200 ppm of propylene. I–V studies show a non-linear relationship. The slope of the curves around zero current matches the resistances measured by ac impedance. The controlled interface sensor design facilitated impedancemetric and potentiometric sensing schemes.