Sensing properties of impedancemetric solid-electrolyte NOx Sensor using perovskite-type lanthanum manganite-based receptor

Abstract

Solid-state impedancemetric NOx sensor devices composed of the perovskite-type oxide (La0.8A0.2MnO3; A = La, Na, K) as a receptor material and a Li1.5Al0.5Ti 1.5(PO4)3(LATP) disc as a solid-electrolyte transducer were investigated for the detection of NOx (NO and NO 2) in the range of 100-500 ppm at 400??C. The lanthanum manganite/LATP-based sensor devices showed NOx sensing responses that could be divided into two components of resistance and capacitance. While the sensitivities to NOx were largely affected by the type of receptor material used, the La0.8K0.2MnO3/LATP-based impedancemetric sensor element showed excellent NO sensing properties. FT-IR measurements revealed that the interaction between NO and La0.8K 0 2MnO3 was the strongest among the receptor materials.