Balancing Reactant Adsorption for Ultra-Stable Electrocatalytic Methanol Oxidation Reaction

The practical application of the electrocatalytic methanol oxidation reaction (EMOR) has long been hindered by the lack of active and stable catalysts. Herein, we report a unique dealloyed PtMn catalyst on carbon cloth (d-PtMn/CC) characterized by a compressively strained Pt surface and a Mn concentration-gradient core. This d-PtMn/CC catalyst demonstrates EMOR activity that is 7–14 times higher than that of conventional Pt/CC catalysts in all-pH electrolytes, while exhibiting exceptional resistance to catalytic poisoning over a broad potential range of 0.4 to 1.2 V vs. RHE. When employed in direct methanol fuel cells, it achieves 111.6 mW cm−2 for over 10 hours at ultralow 0.59 mgPt cm−2, substantially outperforming commercial Pt/C catalysts. Comparative analyses of adsorbed reactants/intermediates revealed that imbalanced adsorption of reactants on the catalyst surface is the primary cause of EMOR poisoning. The d-PtMn/CC catalyst, benefiting from surface compressive strain and ligand effects, maintains balanced reactant adsorption over the wide potential range, thereby achieving ultra-stable EMOR performance. These findings not only resolve the longstanding controversy regarding EMOR poisoning mechanism but also identify the effectiveness of the “ligand + surface strain” strategy in DMFCs, facilitating its practical applications.