Surface manipulation of a triple-conducting cathode for protonic ceramic fuel cells to enhance oxygen reduction activity and CO2 tolerance

One of the main obstacles limiting the performance of protonic ceramic fuel cells (PCFCs) is the sluggish kinetics of the oxygen reduction reaction (ORR) at reduced temperatures. Here, the surface manipulation of a triple-conducting cathode BaCe0.5Pr0.3Y0.2O3-delta (BCPY) by an efficient catalyst coating PrNi0.5Co0.5O3-delta (PNC) to enhance the ORR activity and CO2 tolerance is reported. The developed PNC-coated BCPY cathode achieves the polarization resistance of 0.25 and 1.00 Omega cm(2) at 600 and 500 degrees C, respectively, approximately 1/5 of that for the pristine BCPY cathode (0.99 and 4.79 Omega cm(2)), while maintaining an excellent CO2 tolerance. The single cell on a BaZr0.8Yb0.2O3-delta electrolyte also exhibits a high peak power density of 0.79 W cm(-2) at 700 degrees C and a stable operation for 200 h at 600 degrees C. Such high ORR activity is mainly attributed to the synergistic effect of BCPY support and PNC nanoparticles. Namely, BCPY provides a triple-conducting path (mainly protons), and PNC nanoparticles facilitates surface oxygen exchange and steam adsorption/desorption processes due to the enriched surface oxygen vacancies. This study will provide a new design strategy for developing high-performance PCFCs cathode.(c) 2023 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

This study reports the surface manipulation of a triple-conducting cathode to enhance the oxygen reduction reaction (ORR) activity and CO2 tolerance in protonic ceramic fuel cells (PCFCs). The addition of an efficient catalyst coating significantly improves the ORR activity and reduces the polarization resistance of the cathode, while maintaining CO2 tolerance.