Immobilization of β-cyclodextrin onto the surface of electrospun fibers as rapid and highly efficient adsorbent with good recyclability

It is still a big challenge to obtain adsorbents with high adsorption rate and improved adsorption capacity. Herein, we report a novel electrospun fibers adsorbent modified with carboxylated-β-cyclodextrin (CB-β-CD) molecules for the rapid and efficient removal of phenolphthalein (PHP) from water. First, CB-β-CD is synthesized by esterification of β-CD with succinic anhydride. Subsequently, by means of polydopamine (PDA) coating rich in amine groups, CB-β-CD is covalently bonded onto the surface of poly(vinylidene fluoride)@polystyrene/PDA (PVDF@PS/PDA) fibers through the amide linkage to obtain PVDF@PS/PDA/CB-β-CD fibers adsorbent. XPS, WCA and thermal properties results suggest that large amounts of CB-β-CD molecules hang over the surface of PVDF@PS/PDA/CB-β-CD fibers and the cavities of CB-β-CD molecules are well preserved, thus providing more sites to form inclusion complexes with guest molecules. The adsorbent exhibits excellent adsorption properties for PHP, with a saturation adsorption capacity of 39.97 mg/g after 10 min, which is superior to other reported adsorbents containing β-CD. Moreover, PVDF@PS/PDA/CB-β-CD shows good recyclability and highly selective adsorption of PHP, which has potential applications in molecular recognition, organic molecules separation, and water purification. The developed method provides a new strategy for immobilizing more β-CD molecules onto the surface of composite materials to endow superior comprehensive performances. [Display omitted] •We fabricate a novel fibrous adsorbent with amounts of β-CD molecules located on the surface of electrospun fibers.•Carboxylated-β-CD molecules are bonded to the fibers surface by the formation of amide linkage with polydopamine coating.•Rapid and efficient removal of phenolphthalein (PHP) is derived from the designed structural features.•The recyclable adsorbent could selectively extract PHP from binary anionic dyes mixture in the presence of lemon yellow.