An effective praseodymium oxysulfate/Ba0.5Sr0.5Co0.8Fe0.2O3-δ composite cathode with high stability in 10% CO2/air was investigated. The addition of 50 vol.% of the praseodymium oxysulfate shows much better tolerance to CO2, and reduced the polarization resistance of the cathode to 1/3 comparing with that of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF). The CO2–temperature programmed desorption (TPD) and the electrochemical...