Electrochemical performance and superior CO2 endurance of PrBaCo2O6-δ - PrBaCoTaO6 composite cathode for IT-SOFCs

PrBaCo2O6-delta - PrBaCoTaO6 (PBC/PBCT) composites were studied with respect to their chemical and thermomechanical compatibility with ceria electrolyte (SDC), electrical conductivity, electrochemical performance and reversibility at variations of CO2 content in the oxidizing atmosphere. The electrochemical impedance spectra of the composite electrodes were analyzed by the distribution of relaxation times technique. The best properties combination was observed for the 75/25 composite containing 25 wt% of PBCT where polarization resistance did not exceed 0.025 Ohm.cm(2) in the air at 1073 K. Though subjected to some degradation in CO2 rich atmospheres, the 75/25 composite was shown to completely restore its electrochemical activity after annealing in the air at 973 K. (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The chemical and thermomechanical compatibility, electrical conductivity, electrochemical performance and reversibility of PBC/PBCT composites with SDC were studied. The 75/25 composite showed the best combination of properties at 1073 K in air and could completely restore its electrochemical activity after annealing in CO2 rich atmosphere at 973 K.