Double Passivation Water Based Galvanic Displacement Method for Reproducible Gram Scale Production of High Performance Pt-alloy Electrocatalysts.

Abstract

Preparation of large quantities of high performance supported Pt-alloy electrocatalysts is crucial for the faster development and implementation of low-temperature proton exchange membrane fuel cells (PEMFC). One of the prospective nanofabrication synthesis methods is based on the galvanic displacement (GD) reaction. In this work we present a facile, highly reproducible, gram scale, water-based (green) double passivation GD method for the synthesis of carbon supported Pt-M nanoparticles (M being Cu, Ni and Co). It offers (i) great flexibility over the catalyst design such as the choice of the sacrificial metal (M), (ii) variation of the chemical composition of alloy, (iii) variation of total metal loading (Pt+M) on carbon support or (iv) even variation of the carbon support itself. The obtained Pt-alloy catalysts are several times more active compared to a Pt reference and exhibits better stability during accelerated degradation tests performed at 60 oC.