Controlled synthesis of core-shell composites with uniform shells of a covalent organic framework

We report on the controlled synthesis of core-shell structured composites consisting of TAPB-DMTP-COF shells and SiO2, ZnS, or UiO-66 MOF cores. The core seeds were pre-modified with polyvinylpyrrolidone (PVP) to facilitate their dispersion in the reaction solution and with branched polyethyleneimine (BPEI) to trigger an effective heterogeneous nucleation of the imine COF. Under optimized synthetic conditions, uniform COF layer was grown on the modified seeds to yield well-defined core-shell structures with tunable shell thickness.