Au@CeO2 nanoparticles supported Pt/C electrocatalyst to improve the removal of CO in methanol oxidation reaction

Abstract

Direct methanol fuel cells (DMFCs) are emerging as clean and renewable energy sources for global-scale sustainable energy solutions. However, several limitations of the current standard catalyst (platinum supported carbon black: Pt/C) prevent their commercialization. As an effective co-catalyst, Au@CeO2 core-shell structures are greatly advantageous for getting over the remaining hurdles of Pt/C in DMFCs. Herein, we report an efficient approach for the fabrication of electrocatalyst for DMFCs consisting of three components (Pt/C, Au@CeO2 and Pt catalysts) loaded on carbon cloth using spray and electrophoresis deposition methods. The obtained Pt/C-Au@CeO2-Pt electrocatalyst proved to have high electrochemical surface area (ECSA-77.8 m2/gPt) and high methanol oxidation reaction (MOR) activity (1267 mA/mgPt), which were 1.7 and 2.3 times greater than those of Pt/C only (45.6 m2/gPt and 560 mA/mgPt). In addition, the presence of Au@CeO2 nanoparticles can further enhance the stability of the Pt/C-Au@CeO2-Pt electrocatalyst toward the MOR activity. The improved MOR performance of the Pt/C-Au@CeO2-Pt electrocatalyst could be mainly attributed to the production of abundant OHads promoters, reduction of charge transfer resistance and enhancement of Pt catalytic efficient utilization. It helps to wholly oxidize COads intermediate as dominant poisoning species on Pt catalyst, which are often generated during the MOR operation in acidic condition.