Continuity-Engineered Single-Atom Chains Regulate Interfacial Microenvironments for Valorized Alcohol Electrooxidation

Catalytic selectivity is governed not only by active-site identity but also by the interfacial microenvironments surrounding those sites. Although single-atom chains bridge isolated atoms and extended surfaces, whether their atomic continuity can be exploited as a tunable design parameter for chemical synthesis remains unknown. Here we establish continuity engineering as a strategy for programming catalytic microenvironments through a substrate-anchored synthesis platform that enables precise control over one-dimensional single-atom chain architectures. Using ruthenium chains on α-MnO2 as a model system, we construct catalysts with graded continuity and uncover a volcano-type relationship between chain continuity and synthetic performance during benzyl alcohol electrooxidation. The continuity-optimized catalyst achieves >90% Faradaic efficiency for benzaldehyde across a wide potential window in acidic media while sustaining current densities up to 400 mA cm-2. Mechanistic studies suggest that optimal continuity promotes cooperative water activation, generating a hydroxyl-rich interfacial microenvironment that accelerates alcohol dehydrogenation while suppressing overoxidation. The resulting aldehydes can be directly integrated into one-pot bond-forming (C-S/N coupling) transformations. More broadly, atomic continuity emerges as a design variable for programming catalytic microenvironments and controlling selective electrosynthesis.