Catalyst layer operation electrocatalysis

There is more to catalyst layer operation than electrocatalysis, a lot more The design of fuel cell electrodes with high performance, long lifetime, and low cost is about embedding the catalyst, usually the most expensive and least stable material in the cell, into a porous composite host medium. It turns out that material selection and structural design of the host medium is as important as that of the catalyst material itself. 

PtCo, and PtNi, and this was related to the formadon of a Pt-skin layer on the alloy pardcles. However, for Pt alloys with precious metals such as Ru, Os, or Re, the bifunctional mechanism is operative because of the stability of these elements in the Pt surface. With the introduction and evolution of more powerful characterization techniques such as XAS, it has been possible to perform more detailed studies of the crystalline phases present in a catalyst. The work of McBreen and Mukeijee has shown clearly that in Pt-Ru alloys, the Ru increased the Pt d-band vacancies and decreased the Pt-Pt bond distances. The wider conclusion of this work was that a fine-tuning of the electronic structure and the electrocatalysis is necessary in order to design an even more CO tolerant and active catalyst. 

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