Highly durable Sr-doped LaMnO₃-based cathode modified with Pr₆O₁₁ nano-catalyst for protonic ceramic fuel cells based on Y-doped BaZrO₃ electrolyte

Sr-doped LaMnO₃ (LSM) is one of the state-of-the-art cathodes with outstanding chemical stability but suffers from poor electrochemical activity. It is promising that LSM can be used as good cathode for protonic ceramic fuel cells (PCFCs), provided that its catalytic activity can be improved. Herein, we have developed a high-performance and durable LSM-based cathode used for PCFCs with stable Y-doped BaZrO₃ electrolyte. In this work, commercial LSM cathode is mixed with high-performance BaZr_0.85Y_0.15O_3-δ particles. Pr₆O₁₁ nano-catalysts are homogeneously dispersed into the composite cathode, resulting in a significant decrease in the cathode polarization resistance from 0.51 to 0.12 Ω·cm² at 600 °C. The power output improves by ~96% at 600 °C. Distribution of relaxation time analysis indicates that the processes of oxygen adsorption/dissociation and oxygen species diffuse to triple phase boundary sites are significantly promoted by Pr₆O₁₁. Furthermore, the 100 h stability tests show that the modified cathode is extremely stable.