A novel triple-conductive cathode with high efficiency and stability for protonic ceramic fuel cells

The sluggish kinetics of cathodic oxygen reduction reaction is one of the key barriers to the development of protonic ceramic fuel cells (PCFCs), while the appearance of triple-conductive material reported in recent years has brought a new dawn for the commercialization of PCFCs. These materials need to have excellent hydration ability and water tolerance to expand the active sites and prolong the operation lifespan. Herein, a highly efficient and stable cathode material, BaCo0.4Fe0.4Zr0.1Sc0.1O3-$ (BCFZSc) with cubic perovskite structure, is proposed for PCFCs. Electrical conductivity relaxation measurementsreveal that the oxygen surface exchange coefficient of BCFZSc can reach the value of 1.8 x 10-3 cm s-1at 700 degrees C, almost an order of magnitude larger than those of most reported cathodes. Applying BCFZSc as cathode, single cell exhibits an excellent peak power density of 1.334 W cm -2 with a small polarization resistance of 0.044 U cm2 at 700 degrees C, and a decent durability over 150 h at 600 degrees C is demonstrated. This research highlights that BCFZSc is a promising candidate for PCFCs cathode.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.