Carbon Catalyst-Support Corrosion in Polymer Electrolyte Fuel Cells: Mechanistic Insights

摘要

In this paper we discuss a novel mechanistic model describing the coupling between the PEFC MEA electro-catalysis and the cathode carbon catalyst-support corrosion. On a physical basis, the model describes the feedback between the instantaneous performance and the intrinsic cathode carbon oxidation process. It allows exploring the impact of the operating conditions and the initial electrodes compositions on the PEFC MEA durability. Some numerical simulations show agreement with experimental knowledge already reported in literature: in particular, when the anode chamber is partially exposed to oxygen (induced by PEM crossover or fuel starvation), cathode thickness decrease and cell potential decay are predicted. Furthermore, we found that cathode damage increases as platinum loading increases and as platinum nano-particles size decreases. On the basis of our modeling approach we propose, and experimentally validate, the use of anodic CO injection as a way to mitigate cathodic carbon corrosion in in-house elaborated model MEAs.