Quenching-induced surface reconstruction of perovskite oxide for rapid and durable oxygen catalysise

Rapid degradation of catalytic activity for oxygen reduction reaction has become key factor in restricting practical applications of perovskite oxide in solid oxide fuel cells. Herein, quenching is disclosed to be an effective method to bring rapid and durable oxygen catalysis of perovskite-structured Pr0.5Ba0.25Ca0.25CoO3-delta. The quenching processing, cooling rate is around 8000 times higher than that of traditional annealing process, could turn the output power density of single cells from the decay process with a rate of 17.1% into an upsurge process with a rate of 18.4%, resulting in a stable power density of 0.72 W cm-2. This relates to a large number of point defects, dislocations, disorder and nanocrystalline domains are formed in perovskite oxides by quenching. These chemical defects can drive cationic diffusion to the surface indiscriminately, forming electroactive perovskite-structured nanoparticles. This work provides a new technology and concept to optimize the performance of perovskite-structured oxygen catalysts.