Performance-enhanced direct ammonia protonic ceramic fuel cells using CeO2-supported Ni and Ru catalyst layer

Ammonia is an exceptional fuel for solid oxide fuel cells (SOFCs), because of the high content of hydrogen and the advantages of carbon neutrality. However, the challenge lies in its unsatisfactory performance at intermediate temperatures (500-600 degrees C), impeding its advancement. An electrolyte-supported proton-ceramic fuel cell (PCFC) was fabricated employing BaZr0.1Ce0.7Y0.2O3-delta (BZCY) as the electrolyte and Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCF) as the cathode. In this study, the performance of PCFC using NH3 as fuel within an operating temperature range of 500-700 degrees C was improved by adding an M(Ni,Ru)/CeO(2 )catalyst layer to reconstruct the anode surface. The electrochemical performance of direct ammonia PCFC (DA-PCFC) were improved to different extents. Compared to H-2 as fuel, the degradation ratio of peak power densities (PPDs) of Ni/CeO2-loaded PCFC fueled with NH3 decreased at 700-500 degrees C, with a decrease to 13.3% at 700 degrees C and 30.7% at 500 degrees C. The findings indicate that Ru-based catalysts have a greater promise for direct ammonia SOFCs (DA-SOFCs) at operating temperatures below 600 degrees C. However, the enhancement effect becomes less significant above 600 degrees C when compared to Ni-based catalysts.