The Preparation And Performance Study Of Functional Adsorption Materials Based On Graphene

With the rapid development of science and technology,human’s living standard has been continuously improved.Meanwhile,the environmental pollution is getting more and more serious.The polluted water,containing a large number of heavy metal ions and organic pollution,is seriously harmful to human health.Such toxic substances can cause cancer and be fatal.Therefore,how to deal with these industrial and domestic waste water has become an urgent problem that need to be solved.One of the most common techniques is adsorption,which is cheap,convenient and no secondary hazard.Graphene has become one of the most popular adsorbents because of its unique physical and chemical properties.However,in dealing with complex and diverse pollutants,the adsorption performance of graphene could be poor.So it is urgent to modify graphene with different methods to improve its properties in order to be applied in different conditions.The main work of this paper is to synthesize a series of graphene-based composite adsorbent materials and study their adsorption properties toward different pollutants.The details are as follows:1.By free radical polymerization and molecular imprinting technology,the composites based on polyisopropyl acrylamide（PNIPAm）and graphene oxide（GO）were synthesized,which have two functional adsorption locations.The morphology and structure of materials were characterized by SEM,FTIR and TGA.Through a series of adsorption experiments,the adsorption properties of the compound materials on 4-nitrophenol and lead ions and the recovery ability of the two different pollutants were studied.The results showed that GO/PNIPAm not only has excellent adsorption performance for 4-NP and Pb²⁺simultaneously,but also can separate the two kinds of pollutants by different desorption methods and these would not mix with each other.In addition,the adsorption mechanism of composite materials was investigated by means of Zeta potential,BET and XPS.2.Three-dimensional core-shell structure composite materials with petal shape were synthesized by a pot self-assembly method.This novel composite material is based on the metal oxide Co₃O₄,and the reduced graphene oxide（rGO）shell.By means of XRD,Raman and othes,the material was characterized,and the mechanism of the self-assembly course was studied.The self-assembly process was studied by means of SEM and TEM.A series of adsorption experiments were conducted to investigate the adsorption performance of Co₃O₄@rGO on Sb（III）and Sb（V）.Theresults showed that the adsorption properties of composite materials were significantly improved compared with that of pure rGO and commercial Co₃O₄.The adsorption mechanism of Co₃O₄@rGO was investigated by XPS.3.The aerogel materials with three-dimensional structure were obtained by combining zirconium dioxide with reducd of graphene oxide.The morphology,crystallinity and structure of the materials were characterized by SEM,TEM,FTIR and Raman.FTIR and Raman et al.showed that rGO and zirconia were composited successfully.The adsorption performance of rGO/ZrO₂ on phosphate was studied by adsorption experiment.The results showed that the maximum adsorption capacity was36.98 mg/g and the adsorption process is exothermic.After 3 cycles,the material still retained 92.8%adsorption performance.In addition,the adsorption mechanism of materials was studied by XPS.