Carbon Corrosion of Catalyst Layer

Catalyst carbon support is thermodynamically unstable at PEMFC operating eonditions. Carbon corrosion can result in degradation of the catalyst layer. 

Electrochemical corrosion of carbon material in aqueous acid electrolytes could follow the reaction  

The corrosion rate of carbon can be accelerated in flie presence of Pt on the carbon surface. Oxidation of carbon in the presence of Pt could be accelerated by the following radical reactions [96]  

In acid electrolytes, the mechanism of electrochemical carbon corrosion is generally thought to proceed via a three-step process involving a 4-electron 

The final step of the corrosion process (Step 3) is the formation of carbon dioxide. 

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