Interface engineering of Pt-based catalysts toward enhanced methanol oxidation in direct methanol fuel cells

Direct methanol fuel cells (DMFCs) are promising power sources, but their practical performance remains limited by sluggish methanol oxidation, CO poisoning, Pt-site degradation, and low Pt utilization. This review critically examines Pt-centered interface engineering for the methanol oxidation reaction (MOR) in DMFC anodes. First, MOR pathways, performance descriptors, in situ and operando methods, and the factors governing the transfer of half-cell activity to DMFC output are assessed. Representative catalysts are then compared according to the dominant kinetic or degradation limitation addressed by their local interfaces, covering adsorption regulation, pathway control, oxygen-species cooperation, Pt-site retention or regeneration, and cooperative low-Pt utilization. The analysis assigns the dominant function of multifunctional interfaces, evaluates that function using process-specific evidence, and determines whether it survives working-state evolution and membrane electrode assembly integration. Cross-case comparison shows that material class does not uniquely define function and that similar activity, CO tolerance, or durability may arise from different mechanisms. It further distinguishes suppression of adsorbed CO (CO ads) formation from oxidation of pre-adsorbed CO ads , nominal oxophilicity from verified water activation, and structural retention from functional retention and controlled regeneration. Finally, problem-matched design rules are proposed for efficient, low-Pt, and durable DMFC anodes.