Synthetic control of topology connectivity is the crowning achievement for covalent organic framework(COF)fabrications.Although a large number of one-,two-,and three-dimensional(1D,2D,and 3D)COFs have been reported,th...Synthetic control of topology connectivity is the crowning achievement for covalent organic framework(COF)fabrications.Although a large number of one-,two-,and three-dimensional(1D,2D,and 3D)COFs have been reported,their topology structure constructions are restricted to the use of symmetric monomers with the purpose of increasing the crystallinity and/or porosity.Herein,three imine-linked COFs with different topology nets(namely,sql-b and sql-c)were constructed by symmetric variation of monomers via the condensation of a tetra-amine monomer with a D2h-symmetry and lower C_(2v)-symmetric dialdehyde monomers,bearing a phenolic hydroxyl group at different positions.The results indicated that a reasonable introduction of the phenolic hydroxyl group could effectively tune the topological structure of COFs at the molecular level during the crystallization stage.Particularly,the remarkable difference in the dye uptake ability between these COF materials indicated that the fabricated specific pore geometries,as well as different steric hindrance and H-bonding interactions,played a pivotal role in accessing molecules in the solution.Therefore,this work might boost the explorations of COF materials with expected topologies and pore geometries from conventional monomers through bottom-up synthesis methodology by molecular designing and engineering.展开更多
基金supported by the Natural Science Foundation of Fujian Province,China(grant no.2022J01086).
文摘Synthetic control of topology connectivity is the crowning achievement for covalent organic framework(COF)fabrications.Although a large number of one-,two-,and three-dimensional(1D,2D,and 3D)COFs have been reported,their topology structure constructions are restricted to the use of symmetric monomers with the purpose of increasing the crystallinity and/or porosity.Herein,three imine-linked COFs with different topology nets(namely,sql-b and sql-c)were constructed by symmetric variation of monomers via the condensation of a tetra-amine monomer with a D2h-symmetry and lower C_(2v)-symmetric dialdehyde monomers,bearing a phenolic hydroxyl group at different positions.The results indicated that a reasonable introduction of the phenolic hydroxyl group could effectively tune the topological structure of COFs at the molecular level during the crystallization stage.Particularly,the remarkable difference in the dye uptake ability between these COF materials indicated that the fabricated specific pore geometries,as well as different steric hindrance and H-bonding interactions,played a pivotal role in accessing molecules in the solution.Therefore,this work might boost the explorations of COF materials with expected topologies and pore geometries from conventional monomers through bottom-up synthesis methodology by molecular designing and engineering.