Enhanced stability of ammonia-fed protonic ceramic fuel cells via infiltration of Co-Fe catalyst

In this work, Co-Fe catalysts of different molar ratios are infiltrated into protonic ceramic fuel cell (PCFC) to improve the efficiency of ammonia cracking and cell stability. The degradation rate at 600 degrees C decreases by as high as 88 % under a current density of 625 mA cm-2, proving the effectiveness of infiltrating Co-Fe catalysts. The postmortem analysis indicates that the infiltrated Co-Fe trends to accumulate to Ni particles in the anode and the synergism of Ni, Fe, and Co contributes to the improvement of structure integrity and cell stability in ammonia. We find that the structure evolution corresponding to cell degradation started from the regions near the anode functional layer and the separation of electrolyte grains could be regarded as the failure initiation for NH3-fed PCFC. Both electrochemical stability test and the microstructural observation suggest that a decoration of Co to Fe ratio of 1:1 is more beneficial for NH3-fed PCFC.