Monolayer covalent organic frameworks (COFs) featuring reversible linkages have emerged as promising platforms for dynamic structural reconfiguration. However, achieving programmable depolymerization and reconstruction of robust imine COFs remains a significant challenge. Here we present an "electric-field-mediated molecular scalpel" strategy that combines a localized electric field with bias-responsive boronic acid molecules to achieve localized C═N bond cleavage and nanoscale reconstruction, enabling precise patterning of in-plane imine/boroxine COF hybrid framework. In situ STM reveals a gradual depolymerization mechanism. Kinetic analysis, liquid-phase atomic force microscopy (AFM), nuclear magnetic resonance (NMR), and molecular dynamics (MD) simulations collectively validate a new electric-field-mediated interfacial reconfiguration mechanism of "adsorption-activation-transformation". In this process, boronic acid molecules compete for surface sites, destabilizing the imine lattice and promoting its depolymerization. This work provides the first (sub)molecular-level insight into the dynamic depolymerization of imine COFs and, with nanometer precision, enables the construction of in-plane hybrid framework between imine and boroxine COFs, thereby establishing a generalizable framework for electric-field-mediated nanoscale molecular engineering.
Feng et al. (Fri,) studied this question.