CO2 sensing characteristics of Sm1-xBaxCoO3 (x = 0, 0.1, 0.15, 0.2) nanostructured thick film

SmCoO₃ gas sensor has been developed with high sensitivity for CO₂ gas by doping Ba. Nanostructured SmCoO₃ and Sm1-xBaxCoO₃ (x = 0, 0.1, 0.15, 0.2) were obtained by EDTA-Glycol method. The operation temperature falls and sensitivity increases from 425 to 370°C when Ba concentration in SmCoO₃ changes from x = 0 to x = 0.1. Ag impregnation over Sm_0.9Ba_0.1CoO₃ sensor, on exposure to CO₂ at about 360°C showed an increased sensitivity as well as the response time also decreases. The possible CO₂ sensing mechanism is proposed on the basis of available literatures.