Study On The Preparation And Adsorption Properties Of Graphene Oxide-based Nano-hybrid Materials

With the development of industry and textile industry,solving the problem of water pollution caused by heavy metal ions and organic dyes has always been one of the problems plaguing the world.Although traditional processing methods have certain effects,the lower processing efficiency,higher energy consumption and the potential of secondary pollution have limited their further development.Adsorption as an important method of dealing with heavy metal ions and organic dyes in wastewater,due to its unique advantages,becomes one of the hot spots in water treatment research currently.In this paper,we aim to make use of the advantages of graphene-based adsorbents to prepare new adsorbent materials with cost-effective,stable,and easy to reuse.Cu(?)and methylene blue were used as typical metal ion and organic dye contaminants to measure the adsorption performance of the prepared adsorbent.And we investigated the adsorption mechanism to research the effect of space structure and adsorption active sites on the adsorption performance of graphene oxide-based adsorption materials.First,as for the problem that the existing of intermolecular forces between graphene oxide(GO)nanosheets are liable to lead to ?-? stacking,this experiment supports the adjacent graphene oxide sheets by introducing multi-walled carbon nanotubes(MWCNTs)to form a GO/MWCNTs frame structure with larger surface area.In order to facilitate the recycling of adsorbent materials and better fixation of the connected GO and MWCNTs,the GO/MWCNTs/Fe3O4 ternary nanocomposites were obtained by loading GO3O4 nano-loaded on GO/MWCNTs framework.All the nanocomposites were characterized by XPS,XRD,SEM and so on.It was found that this porous GO/MWCNTs/Fe3O4 ternary nanocomposite can well inhibit the ?-?stacking between GO sheets and expose more active sites.Due to the unique structure of the GO/MWCNTs/Fe3O4 ternary nanocomposites and the synergy between the components,it has a very good effect on the removal of Cu(?)and methylene blue in aqueous solution.In addition,in the contaminated water source where Cu(?)and methylene blue coexist,the ternary composite material can effectively remove both contaminants at the same time.The adsorption process of Cu(?)and methylene blue by the ternary nanocomposite conformed to the Langmuire adsorption isotherm model.Then,in order to investigate the influence of the active sites on the graphene oxide-based adsorption material,PGO/Fe3O4 magnetic adsorption materials were obtained through hydrothermal method where the three-dimensional(3D)PGO was acting as a substrate and loading Fe3O4 nanoparticles.The PGO/Fe3O4 magnetic adsorbents were modified by co-grafting with dopamine(DA)and silane coupling agent(KH550)to obtain PGO/Fe3O4/PDA and PGO/Fe3O4/PDA+KH550 nanocomposites.The co-grafting of DA and KH550 can obtain more active sites on the adsorbent surface than pure DA modification.In this paper,the morphological features and chemical composition of modification magnetic adsorption materials were analyzed through FTIR,X-ray photoelectron spectroscopy(XPS)and scanning electron microscopy(SEM).The adsorption properties and adsorption mechanism of the magnetic adsorption materials before and after modification were studied by adsorbing Cu(?)and methylene blue.The maximum adsorption capacity of PGO/Fe3O4/PDA+KH550 hybrid materials for Cu(?)can reach 93.20 mg/g,and the maximum adsorption for methylene blue can reach 602.41 mg/g.