Fast Cryomediated Dynamic Equilibrium Hydrolysates towards Grain Boundary-Enriched Platinum Scaffolds for Efficient Methanol Oxidation

Abstract

Although platinum nanocrystals have been considered as potential electrocatalysts for methanol oxidation reaction (MOR) in fuel cells, the large-scale practical implementation has been stagnated by their limited abundance, easy poisoning, and low durability. Here, grain boundary-enriched platinum (GB-Pt) scaffolds are produced in large scale via facilely reducing fast cryomediated dynamic equilibrium hydrolysates of platinum salts. Such plentiful platinum grain boundaries are originated from the fast fusion of short platinum nanowires during reduction of the individually and homogeneously dispersed platinum intermediates. These grain boundaries can provide abundant active sites to efficiently catalyze MOR and meanwhile enable to oxidize the adsorbed poisonous CO during the electrocatalytic process. As a consequence, the as-synthesized GB-Pt scaffolds exhibit an impressively high mass activity of 1027.1 mA mgPt−1 for MOR, much higher than that of commercial Pt/C (345.2 mA mgPt−1), as well as good stability up to 5000 cycles. We are confident that this synthetic protocol can be further extended to synthesize various grain boundary-enriched metal scaffolds with broad applications in catalysis.