Strain-Modulated Platinum – Palladium Nanowires for Oxygen Reduction Reaction


Abstract image

The anti-alloying effect of alloy nanocatalysts can be effectively manipulated by selecting their physical properties (ensemble, geometric and ligand effects) to obtain optimal surface structure and compositions for Proton Exchange Fuel Cell (PEMFC) application. Here, highly catalytic platinum – palladium nanowires (PtNPD100–N NWs) with sophisticated retinal strain and Boerdijk-Coxeter helix type morphology are synthesized by surfactant-free, thermal single-phase solvent method. X-ray diffraction results show that PtNPD100–N NWs are subject to (111) façade and their reduction or extension can be modified by graph alloying parameters. The electrochemical results show that their high catalytic activity is correlated with the reduction of horns, facades and bimetallic compositions, which show higher activity when the Pt and Pd ratio is ∼78: 22, which further supports the DFT results. Compared to Nanoparticles, Platinum-Palladium Alloy Catalyst with Similar Metal Compositions (PtNPD100–N Np), PtNPD100–N NWs significantly improve electrocatalytic activity and stability for the oxygen reduction reaction. These findings open up new strategies for controlling active and stable alloy nanocatalysts with controlled compositions.

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