The Carbon Corrosion Resistance of Mesoporous PtIr Catalysts in Proton Exchange Membrane Fuel Cells

Abstract As the main degradation mechanism, carbon corrosion behavior plays an important role to deteriorate the durability and lifetime of PEMFCs. For addressing the issue, we synthesized a novel type of mesoporous PtIr alloy catalyst through the self‐assembled composite micelles made of PS‐b‐P2VP‐b‐PEO triblock copolymer and metal acid ions (PtCl₆²⁻ and IrCl₆²⁻). The strength of large ECSA and high limited current density on PtIr_{85 : 15} and PtIr_{75 : 25} catalysts could be attributed to the uniformly ordered mesoporous structure. It is beneficial to the sufficient exposure of reactive sites and the diffusion of reactants and products. The corresponding PtIr/C alloy catalysts were obtained to deposit PtIr alloys on Vulcan XC 72R. After stress cycling, the increase rate of double‐layer capacitance is the slowest on PtIr_{75 : 25}/C and keeps the minimum values. Moreover, the increase speed of Q/HQ peak is also associated with the increased Ir content in catalyst. Here, incorporation with Ir atom has been proved as an effective method to protect the carbon corrosion behaviors.