Metal-organic interface engineering for coupling palladium nanocrystals over functionalized graphene as an advanced electrocatalyst of methanol and ethanol oxidation.

Adjusting the surface structures and electronic structures of metal nanocrystals (NCs) by the metal-organic interface interaction is an emerging strategy to enhance their electrocatalytic behavior. In this work, the d-phenylalanine-functionalized graphene (DPHE-GS) anchoring Pd NCs (denoted as Pd/DPHE-GS) was fabricated via the diazo-reaction followed by a simple chemical reduction. Owing to the metal-organic interface interaction between Pd NCs and DPHE, the size, distribution and electronic structures of Pd NCs on the surface of DPHE-GS can be adjusted. Therefore, the Pd/DPHE-GS shows the highest electrocatalytic activity and the most robust long-term durability and stability towards methanol and ethanol oxidation reaction (MOR and EOR) compared to the commercial Pd/C and other counterparts. This work presents an effective interface engineering strategy to enhance electrocatalytic property.