Layer-by-layer assemblies of highly connected polyelectrolyte capped-Pt nanoparticles for electrocatalysis of hydrogen evolution reaction

Abstract

Herein we present a simple one-step method to produce polyelectrolyte-capped Pt nanoparticles able to be assembled into layer-by-layer arrays with a linear dependence of the amount of deposited material on the number of dipping cycles. The resulting supramolecular films where fully characterized by AFM, XPS and ATR-FTIR. The electrochemical evaluation by cyclic voltammetry showed good electrochemical connection between the nanoparticles in both acidic and neutral solutions. The films assembled on graphite electrodes showed catalysis of the H2 production and the interconnection between nanoparticles proved to be effective up to 20 bilayers. Results presented here reveal an easy procedure to obtain stable arrays of well-dispersed electroactive 2 nm-diameter Pt nanoparticles on a variety of substrates with direct potential applications in energy conversion devices.