Carbon Corrosion in Fuel Cells-Fundamentals and Mitigation Approaches

At present, Pt nanoparticles (NPs), supported on a high specific surface area carbon are widely used as proton exchange membrane fuel cell (PEMFC) catalysts. However, carbon is not thermodynamically stable under the operating conditions in PEMFCs, and the electrochemical oxidation of carbon is accelerated at elevated temperature and potential. The performance degradation is mainly caused by Pt detaching or agglomerating due to the weakened interaction between Pt and the carbon support, which leads to the loss of Pt surface area. Therefore, carbon corrosion in the catalyst is one of the main reasons that limit the lifetime of the PEMFC and there are three main conditions that cause carbon corrosion, including startup and shutdown, water flooding, and long-term aging. This chapter presents an overview of the causes and consequences of the carbon corrosion mechanism and summarizes the corresponding mitigation strategies for various operating conditions.