Optimization of ink composition based on a non-platinum cathode for single membrane electrode assembly proton exchange membrane fuel cells

► Effect of catalyst ink formulation on performance and stability is studied. ► XPS is used to study surface chemistry of various ink formulations. ► Statistical structure-to-property relationship is built by PCA. ► Better performance is linked to pyridinic N, N bounded to Co and CoO particles. ► Higher stability is associated with preserved moieties from carbon black and ionomer.