Following dissolved nickel from advanced Pt-alloyed ORR catalysts in a real fuel cell

The main bottleneck in proton exchange membrane fuel cell (PEMFC) is the inefficient catalyst for cathodic oxygen reduction reaction (ORR) limiting both maximum current density and efficiency. Shape-controlled octahedra oh-PtNiIr nanoparticles (NPs) exhibit a 3-fold increment in activity when compared to commercial Pt catalysts. However, in the membrane electrode assembly (MEA) of a fuel cell, these catalysts suffer from dissolution. Compared to protons, nickel cations have a higher affinity for sulfonic acid groups in the PEM and when dissolved out of the nanoparticle, they might migrate into the membrane, reducing the overall performance of the FC. We designed an innovative cell that will enable us to perform operando XAS depth profiling of the MEA and thus follow nickel cations in the membrane. This information is important for our industrial partner Johnson Matthey as it must be addressed to improve performance thus helping with decarbonization goals of the EU.