Boosting Methanol Electrooxidation on Pt/C with a Metal-Free Nitrogen-Doped Carbon Cocatalyst via the Ripple Effect.

Platinum-based catalysts are the core components for methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). Although platinum catalysts on nitrogen-doped carbon (NC) show promising MOR activity, the coupled variation between Pt and NC during synthesis obscures their individual contributions. Herein, a solid-phase interface reaction (SIR) successfully decouples their interactions, clarifying the role of each component. We define the ripple effect as the long-range electronic modulation induced by Pt-N coordination, which modulates the electronic state of Pt active sites in a long-range manner and thus significantly accelerates MOR reaction kinetics. Based on this, a metal-free catalytic promoter was developed. When combined with commercial 5 wt% Pt/C, the resulting Pt/C@NC-6hr composite exhibits 1.67 times and twice the mass activity of 5 and 20 wt% Pt/C. Furthermore, statistical results indicate that the mass activity derived solely from the Pt on NC is 4.74 times higher than that of the original 5 wt% Pt/C catalyst, demonstrating a remarkably substantial activity enhancement. After 3600 s chronoamperometry at 0.75 V (vs. RHE), it maintains superior current density. This work elucidates the mechanism of microenvironment-enhanced Pt catalysis via the ripple effect and offers a practical strategy for improving commercial Pt/C.