Electro-catalytically active Au@Pt nanoparticles for hydrogen evolution reaction: an insight into a tryptophan mediated supramolecular interface towards a universal core–shell synthesis approach

Abstract

We report an eco-friendly, one-pot, room-temperature method for the rapid synthesis of electrocatalytically active Au@Pt (50 nm) bimetallic nanoparticles via a tryptophan (Trp) mediated supramolecular interface in an aqueous environment. Our results demonstrate a simple universal approach for high shell–metal loading where a pre-stabilized tryptophan polymerized-Au core serves as a template to facilitate subsequent deposition of Pt. We observed that the amine-stabilized poly-Trp bi-layer has an enhancing effect on the electrocatalytic potential of Au@Pt NPs by the virtue of an amine stabilized interface, thereby enhancing the HER activity over glassy carbon electrodes. Several characterization techniques were used to confirm the inherent core–shell morphology of the resulting Au@Pt NPs. This Trp mediated facile green synthesis strategy has the potential to synthesize an array of Au-core containing bimetallic nanoparticles with enhanced catalytic activity and stable structure integration.