Enhancing power density in protonic ceramic fuel cells with porous interlayer

This study addresses the critical need to enhance the performance of protonic ceramic fuel cells (PCFCs) by engineering a porous interlayer between the cathode and electrolyte. A porous interlayer composed of the electrolyte material, barium cerium zirconium yttrium oxide electrolyte (BaCe 0.6 Zr 0.2 Y 0.2 O 3-δ , BCZY) was prepared at various calcination temperatures to optimize its microstructure. With the optimized calcination temperature of 1350 °C, the porous interlayer forms effective contact with the lanthanum strontium cobalt ferrite cathode (La 0.8 Sr 0.2 Co 0.8 Fe 0.2 O 3-δ , LSCF), enhancing the number of triple-phase boundary reaction sites for oxygen reduction. A PCFC with an optimal porous interlayer achieved a peak power density of 517 mW/cm 2 at 800 °C, representing an 11.6 % improvement over the fuel cell without the porous interlayer. This enhancement is attributed to the extension of electrochemically active areas, which reduces polarization resistance by 23.8 %. • A porous interface layer is fabricated using the electrolyte calcine at lower temperatures. • The porous interface layer forms effective 3D contact with the cathode. • The best calcination temperature was found to 1350 °C. • The peak power density achieved 517 mW cm −2 , an 11.6 % improvement.