Functional Composites Based On Graphene Oxide For Fast Removal Of Organic Pollutants In Water

The organic pollutants in aquatic environment cause serious harmful impacts on the existence and the health of human beings.Researchers have been paying attention to how to remove organic pollutants in water fast,efficiently and easily for a long time.Graphene oxide with large specific surface area,abundant functional groups,simplicity of functionalization and low cost has been applied in water purification extensively.Cyclodextrins,the commonest host molecule,are usually used as absorbents for organic pollutants because of their hydrophobic cavities and lots of hydroxyls.Metal-Organic Frameworks(MOF)are outstanding absorbents for their numerous varieties,large specific surface area,large porosity and tunable chemical structure.But their composites formed with graphene oxide for water purification are relatively new,especially in filtration field.In order to make full use of the advantages of these materials for water purification,we synthesized the cyclodextrin functionalized reduced graphene oxide membrane and the composite of graphene oxide and MOF.Moreover,we also make innovative explorations in their application for high speed filtration to remove organic pollutants in water.(1)The cyclodextrin-modified reduced graphene oxide membrane with novel microstructure and ultrahigh flux has been prepared successfully.This membrane showed great removal performance for organic pollutants.Reduction created an approximate frictionless surface of GO to let water move rapidly during the filtration process.The special CD cluster chemically anchored on RGO sheets prevented the stack of RGO effectively,and its cavity and carried-OH groups could capture organic pollutants fast and completely.The CD-RGO membrane with special structure exhibits promising filtration applications with great removal ability and high speed,and the designing thought in this work could provide reference to construct other new materials.(2)Composite of graphene oxide and carboxyl functionlized iron terephthalate MIL-53(Fe)type MOF has been synthesized.We confirmed the covalent nature of interactions between graphene oxide and MOF by different spectrums.The composite has plicate surface and large specific surface area,and can remove organic dyes in water by filtration fast.The removal ability comes from the nanoporous of MOF and high electron density provided by carboxyl groups.We believe that our studies will be helpful to obtain new materials based on MOF for water purification.