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

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/g_Pt) and high methanol oxidation reaction (MOR) activity (1267 mA/mg_Pt), which were 1.7 and 2.3 times greater than those of Pt/C only (45.6 m²/g_Pt and 560 mA/mg_Pt). 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 OH_ads promoters, reduction of charge transfer resistance and enhancement of Pt catalytic efficient utilization. It helps to wholly oxidize CO_ads intermediate as dominant poisoning species on Pt catalyst, which are often generated during the MOR operation in acidic condition.