A highly active catalytic cathode La0.8Sr0.2Co0.7Ni0.3O3-δ for protonic ceramic fuel cells: Experimental and computational insights

Protonic ceramic fuel cell (PCFC) is an emerging technology for efficient energy conversion, with which the performance of a cathode with high oxygen reduction reaction (ORR) kinetics is crucial. In this work, we report a glycine-nitrate technique to synthesize a highly active catalytic cathode La 0.8 Sr 0.2 Co 0.7 Ni 0.3 O 3-δ (LSCN). Electrochemical measurement and density functional theory (DFT) simulation are adopted to reveal ORR mechanism. Computational simulations reveal that the presence of oxygen vacancies significantly reduces ORR overpotential by stabilizing reaction intermediates and lowering the proton transfer energy barrier. The fuel cell with LSCN reached the excellent PCFC with a peak power density of 1.62 W cm −2 at 700 °C. Durability testing over 100 h showed no significant degradation, demonstrating the stability of the LSCN cathode. This work provides a path to the rational design of high-performance PCFC cathode. • Peak power density of 1.62 W cm −2 is measured at 700 °C. • Oxygen vacancy in LSCN boost oxygen reduction reaction kinetics. • LSCN cathode shows excellent stability over 100 h.