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. reversible hydrogen electrode (RHE). When employed in direct methanol fuel cells, it achieves 111.6 mW cm −2 for over 10 hours at ultralow 0.59 mg Pt 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. • d -PtMn/CC features a compressively strained Pt surface and a Mn concentration-gradient core. • d -PtMn/CC enhances both EMOR activity and durability by 7–14 times than conventional Pt/CC. • d -PtMn/CC shows excellent performances in direct methanol fuel cells (DMFCs) with all-pH electrolytes. • CH x O y and OH are identified to be toxic species at low and high potentials, respectively. • d -PtMn/CC balances reactants adsorption over 0.4–1.2V vs. RHE, mitigating EMOR poisoning.