High-performance proton ceramic fuel cells using a perovskite oxide cathode surface decorated with CoOx nanoparticles

초록

This study reports on the performance improvement of a protonic ceramic fuel cell (PCFC) after a CoOx nanoparticle treatment has been applied to a PrBa(0.5)Sr(0.5)Co(2-x)FexO(5+delta)(PBSCF) cathode with a perovskite structure. CoOx nanoparticles are deposited on the sintered PBSCF surface using a plasma-enhanced (PE) atomic layer deposition (ALD) process, thereby avoiding any unwanted reactions or phase changes. The CoOx nanoparticles are successfully deposited uniformly onto the entire surface of the porous and complex cathode structure. A constant deposition rate is observed because of the self-limiting characteristics of the ALD process by a thickness difference as a function of a change in the cycle count. In our experiment, the performance of the fuel cells increases by approximately 36 % compared with the untreated cells at an operating temperature of 650 degrees C. In addition, all cells feature long-term stability. Impedance analysis reveals that the CoOx nanoparticle treatment results in a significant polarization and some ohmic loss improvement within all temperature regions. This is due to the synergistic effect with PBSCF and self-catalytic effects. The results imply that the proposed method enables high-performance PCFC fabrication; additionally it helps lowering the operating temperature.

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