Probing CO2 reaction mechanisms and effects on the SrNb0.1Co0.9−xFexO3−δ cathodes for solid oxide fuel cells

Two different mechanisms are proposed to explain the interaction between CO2 and the SrNb0.1Co0.9−xFexO3−δ perovskites. This distinct behavior correlates with the oxygen non-stoichiometry, highlighting the role of oxygen vacancies in promoting the carbonate formation. Moreover, the average metal-oxygen bond energy can be utilized as a good predictor for CO2 resistance.