Synthesis and Characterization of Low Platinum-Cobalt Alloy Cathode Catalysts by Rapid Annealing and Quenching Method for Fuel Cell Applications

Polymer electrolyte membrane fuel cell (PEFC) has tremendous attention due to its unique properties, such as low-temperature operation, high power density, and application of solid electrolyte. Therefore, it is considered as a reliable power sources for transport, residential, and portable applications. However, current PEFC designs encounter problems, such as materials compatibility, fabrication cost, performance degradation, and so forth. Much research has been conducted to enhance the performance and durability of PEFC by improving electrode in which Pt is commonly used. To further improve the performance of electrode, it is important to enhance the Pt catalyst utilization in the electrode. On the other hand, Pt is extremely rare and expensive, that limits the practical application and wide-scale commercialization of PEFC. Low Pt content catalyst and its alloy have great potential to overcome these limitations by lowering Pt consumption, while its high catalytic activity and durability can be maintained in the meantime. Herein we prepared PtCo/C alloys as cathode catalyst by rapid heating and quenching (RHQ) method to investigate the relationship between catalytic activity and annealing temperature. Annealing temperatures are changed from 600-900oC to obtain highly-alloyed small particles. For comparison, commercial PtCo/C catalyst was used as reference. Analyses of the I-V characteristics obtained from PtCo/C catalysts and after ADT test reveal the highest catalytic activity and durability in the case of annealing at 900oC. It is suggested that the high catalytic activity and durability of PtCo/C catalyst can be achieved by providing a high-alloy with smaller particle sizes.