Deposition of MOFs on Polydopamine-Modified Electrospun Polyvinyl Alcohol/Silica Nanofibers Mats for Chloramphenicol Adsorption in Water

Nanofiber mats produced by electrospinning, with the advantages of specific surface area, porosity and chemical tenability, are an ideal support material for deposition of metal-organic framework (MOF) crystals. In this study, four types of MOFs (MIL-53(Al), ZIF-8, UiO-66-NH2 and NH2-MIL-125(TH) were deposited on polydopamine (PDA)-modified electrospun polyvinyl alcohol (PVA)/SiO2 organic-inorganic hybrid nanofiber mats by bulky synthesis. Because of the formation of Si-O-C-O-Si bridges between PVA chains and silica network, electrospun PVA/SiO2 organic-inorganic hybrid nanofiber mats are quite stable in water or organic solvents and at high temperature are suitable as supports for MOFs deposition. The PDA layer, which exhibits a powerful adhesive ability to attach foreign objects, can effectively improve growth of MOFs on the surface of PVA/SiO2 nanofiber mats. The obtained MOF composites combining the unique properties of electrospun nanofibers mats and MOFs particles become flexible and tailorable, greatly expanding the application range of MOFs materials. The synthesized MOF composites were used to adsorb chloramphenicol (CAP) in water. It was found that the four MOF composites could remove CAP from water effectively and MIL-53(Al) composite had the highest adsorption capacity due to the higher specific surface area.