Pseudo-Pt Monolayer for Robust Hydrogen Oxidation

Heteroepitaxial core-shell structure is conducive to combining the advantages of the epilayer and the substrate, creating a novel multifunctionality for catalysis application. Herein, we report a pseudomorphic-Pt atomic layer (PmPt) epitaxially growing on an IrPd-core matrix (PmPt@IrPd/C) as an efficient and stable catalyst for alkaline hydrogen oxidation reaction that exhibits-,29.2 times more mass activity enhancement than that of benchmark Pt/C. The PmPt@IrPd/C catalyst also gives rise to-,25.0 times more enhancement than Pt/C during a 50,000-cycle accelerated stability test. This robust stability originates from the resistance to carbon corrosion owing to the stronger H2O interaction instead of carbon oxide (COx) poison species, and the modulated hydroxyl (OH*) adsorption could inhibit the OH* species from shuffling the surface Pt atoms away from the substrate. Moreover, the anion-exchange membrane fuel cells assembled by PmPt@IrPd/C with an ultralow Pt loading of 0.009 mgPt cm-2 in the anode can deliver a power density of 1.27 W cm-2.

Automated summary

We report a heteroepitaxial core-shell structure that combines the advantages of the epilayer and the substrate, creating a multifunctional catalyst for catalysis application. The pseudomorphic-Pt atomic layer epitaxially growing on an IrPd-core matrix (PmPt@IrPd/C) exhibits significantly enhanced mass activity and stability compared to benchmark Pt/C. The improved stability is attributed to resistance to carbon corrosion and modulated hydroxyl adsorption.