CoP/RGO-Pd Hybrids with Heterointerfaces as Highly Active Catalysts for Ethanol Electrooxidation

ACS Appl Mater Interfaces. 2020 Jun 24;12(25):28903-28914. doi: 10.1021/acsami.0c07703. Epub 2020 Jun 10.

Abstract

The ethanol oxidation reaction is of critical importance to the commercial viability of direct ethanol fuel cell technology. However, owing to the poor C-C bond cleavage capability, almost all ethanol oxidation is incomplete and suffers from low selectivity toward the C1 pathway. Herein, under the support of theoretical calculations that the heterointerfaces between CoP and Pd can reduce the energy barrier of C-C bond cleavage, rich heterointerfaces in CoP/RGO-Pd hybrids were designed to improve ethanol electrooxidation performance through enhancing the selectivity toward the C1 pathway. The experimental results show that the faradaic efficiency of the C1 pathway of CoP/RGO-Pd hybrids is as high as 27.6%, surpassing most reported catalysts in the literature. As a result of this enhancement, CoP/RGO-Pd10 exhibits mass activity as high as 4597 mA·mgPd-1 and specific activity as high as 10 mA·cm-2, which are much higher than those of other Pd-based electrocatalysts.

Keywords: C1 pathway; C−C bond cleavage; cobalt phosphide; ethanol oxidation reaction; heterointerfaces.