Significantly enhanced electrocatalytic activity of Au25 clusters by single platinum atom doping

Abstract

The search for highly active catalysts with low-Pt content to advance the commercialization of fuel cells is continuing to receive ample attention. Herein, we report that by doping a single Pt atom into Au25 to form Pt1Au24 nanoclusters, the electrocatalytic activity for the direct formic acid oxidation (FAO) to carbon dioxide is enhanced significantly. The mass activity of Pt1Au24 (3.7 A mgPt+Au−1) is nearly 12 and 34 times greater than that of Pt nanoclusters and the commercial Pt/C catalyst, respectively. Density functional theory (DFT) calculations and potential-dependent thermodynamic analyses provide fundamental insights into the reaction mechanism illustrating that FAO proceeds through the carboxyl (COOH) intermediate on Pt1Au24. The present study not only develops a novel class of single-Pt atom doped Au nanocluster electrocatalysts for fuel cells with high utilization of Pt, but also provides insight into the mechanism of FAO on Pt-doped Au nanoclusters. Moreover, this study begins to shed light on the structure-activity relationship and helps to provide a strategy to design new catalysts by tuning their catalytic properties at the atomic level.