Proton exchange membrane fuel cells (PEMFCs) represent one of the solutions to the environmental crisis that is arising from the greenhouse gases. The electrocatalyst, whose primary active component is platinum, represents the heart of the fuel cell. Its disadvantage are, however, the high losses resulting from the sluggish kinetics of the oxygen reduction reaction (ORR) on the cathode. Since platinum is a very rare and consequently very expensive metal, optimizing its utilization is essential. In addition, since electrochemical reactions such as ORR take place only on platinum’s surface, we use it in the form of nanoparticles. This also means that all the platinum located in the core of the nanoparticles is poorly utilized. Consequently, we also resort to the use of platinum-alloys, which results in an additional increase of ORR activity per mass of platinum. For this purpose, the National Institute of Chemistry (Department of Materials Chemistry) developed and patented a method of galvanic exchange with double passivation (DP) for electrocatalysts based on platinum-copper alloys. The new method enables uniform distribution of precious metal nanoparticles on the surface of the conductive supporting material. In this work, the method is extrapolation of this method to platinum-cobalt alloys as well as the process optimization of their preparation are presented. Whereas the first part of this works covers the chemical parameters, the second part covers the studying of the engineering parameters. Upon understanding of their mechanisms, computational fluid dynamics (CFD) have been used to predict the scale up of the production as well as the transfer to a smaller half-batch mechanically stirred pilot reactor. In addition, a flow-type reactor has been established, and the aforementioned process transferred to it as well. Finally, the catalysts obtained by the DP method have been compared experimentally with the best commercially available catalysts, thereby demonstrating their competitiveness.
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