Mitigating methanol crossover with self-assembled Pt35-Ru65 catalyst on Nafion surface

► A new approach to mitigate methanol crossover has been proposed. ► A layer of Pt35-Ru65 with a thickness of 87.5 nm deposited on Nafion acts as a methanol barrier. ► MEA with self-assembled Pt35-Ru65 layers suppresses methanol crossover by 22% and improves power density by 48% (at 0.30V) at 80 °C. ► Catalytic reaction, microstructure and low methanol permeability of self-assembly layers affect methanol crossover.