Interfacial Charge Transfer Directing Intermolecular Hydrogen Transfer for On-Surface C–H Activation

Interfacial charge transfer, by sculpting energy level alignment, charge density distributions, and interfacial states, is a key determinant of catalytic and device performance. While the centrality of interfacial charge transfer has been firmly evidenced, its systematic exploitation for designing reaction pathways in on-surface synthesis remains conspicuously underdeveloped. Concurrently, on-surface carbon-hydrogen (C-H) activation continues to rely on thermal treatment or extrinsic components (e.g., gas molecules, metals, and radicals), affording limited selectivity and efficiency. Here, we report a bimolecular hydrogen-atom-transfer (HAT) strategy for on-surface C-H activation by introducing well-defined "hydrogen-acceptor" molecules, whose reactivity is directed via interfacial charge transfer. This approach reveals a controllable intermolecular HAT-driven C-H activation mechanism, establishing a rational design principle for charge-transfer-mediated activation in surface chemistry.