Growth of quinoline-linked covalent organic frameworks on electrospun nanofibers with enhanced adsorption on chlorinated phenols

•A quinoline-linked COFs was synthesized by Povarov reaction between phenylacetylene and imine-linked COFs.•The self-supporting COF-QL-Ph nanofibers displayed the hollow structure and good crystalline.•The self-supporting COF-QL-Ph nanofibers exhibited effective adsorption to chlorinated phenols.•The maximum adsorption capacity of 2,4-DCP on COF-QL-Ph was 616.90 mg g−1.•The hollow structured COF-QL-Ph nanofibers improved the mass transfer process and exhibited the good practicality. Covalent organic frameworks (COFs) have attracted increasing interest as adsorbents in water treatment,but the lack of high-performance adsorbents materials and effective morphological structures limits their practical application. In this work, a novel quinoline-linked COFs (COF-QL-Ph) with high crystallinity was synthesized by post-synthetic-modification (PSM). Firstly, the precursor organic ligands of imine-linked COFs were directly electrospinning with polyacrylonitrile (PAN) solution as the seeded nanofibers. Subsequently, the imine-linked COFs formed from 1,3,5-benzenetricarboxaldehyde (TFB) and 2,6-diaminonaphthalene (2,6-DAN) were grown on the seeded PAN nanofibers. Finally, self-supporting imine-linked COFs hollow nanofibers were obtained by etching the polymeric substrates. These were then transformed into quinoline-linked COF-QL-Ph nanofiber through the Povarov reaction between phenylacetylene and the matrix imine-linked COFs. The resulting COF-QL-Ph nanofibers exhibit a developed hollow structure and high porosity for effective adsorption of chlorinated phenols in water. The adsorption behavior of 2,4-dichlorophenol (2,4-DCP) on COF-QL-Ph nanofibers followed the Langmuir model, and the maximum adsorption capacity was 616.9 mg g−1. The abundant benzene rings and quinoline structures in COF-QL-Ph nanofibers provided a great number of sites for the interaction with 2,4-DCP, which were confirmed by simulation and adsorption characterization. As expected, the self-supporting hollow structure of COF-QL-Ph nanofibers greatly improved the mass transfer rate of adsorbed analytes and accelerated the kinetic process. Furthermore, COF-QL-Ph nanofibers exhibited good structural stability and high recovery performance after six adsorption–desorption cycles. Thus, COF-QL-Ph nanofiber represents a highly promising adsorbent suitable for purifying chlorinated phenols in environmental waters.