基于氧化石墨烯水凝胶的制备及其性能的研究

发布时间：2019-04-23 19:19

【摘要】：氧化石墨烯(GO)是石墨烯的一种重要衍生物,它是一种性能优异的新型碳材料,具有较高的比表面积和表面丰富的官能团,由于其表面存在着大量的羟基、羧基和环氧基等含氧官能团,这为氧化石墨烯的表面功能化修饰提供了反应点。同时这些含氧官能团的亲水性使其能在水中形成稳定的胶状分散体系,对于提高氧化石墨烯复合材料在水中的分散性极其有利。自组装过程是一项将各种纳米级构建模块整合成具有优异性能的宏观材料的实用技术,这些自组装的超分子结构材料具有非常好的物理化学性质并且实际应用价值非常广泛。作为一种新型的自组装纳米功能材料,凝胶是用适当的有机溶剂或水溶剂凝胶化得到的产物,呈有序组装的三维网络结构。本论文采用改进的Hummers法制备了氧化石墨烯,然后经由超声剥离制得了片层结构的氧化石墨烯,最后通过自组装过程设计合成GO-DETA水凝胶以及GO-TETA水凝胶,通过TEM、SEM、TGA、AFM、XRD、FTIR、Raman等对制备出的氧化石墨烯水凝胶的显微结构以及性能进行了研究。通过氧化石墨烯(GO)分别与二乙烯三胺(DETA)和三乙烯四胺(TETA)自组装制得GO-DETA水凝胶和GO-TETA水凝胶对其吸附性能进行研究,本文使用基于氧化石墨烯制备出的水凝胶作为吸附剂对罗丹明B(RhB)、亚甲基蓝(MB)、刚果红(CR)这三种染料和对Cu2+、Pb2+这两种重金属离子分别进行了吸附实验。详细研究了溶液的初始pH和不同质量浓度的水凝胶对吸附性能的影响;此外还对其进行了吸附动力学、吸附热力学实验,以便对其吸附机理进行探讨。结果表明:通过Hummers法制备出的氧化石墨烯具有片状的二维结构,表面有许多的褶皱;通过氧化石墨烯分别与二乙烯三胺和三乙烯四胺自组装制得GO-DETA水凝胶和GO-TETA水凝胶具备褶皱、多孔的三维网络纳米结构;通过对其吸附动力学及吸附热力学分析,可以得知基于氧化石墨烯制备得到的水凝胶对工业废水中染料分子的吸附更符合准二级动力学模型以及Freundlich等温吸附模型。
[Abstract]:Graphene oxide (GO) is an important derivative of graphene. It is a new type of carbon material with excellent properties. It has high specific surface area and rich functional groups on the surface, due to the existence of a large number of hydroxyl groups on its surface. Oxygen-containing functional groups, such as carboxyl and epoxy groups, provide a reaction point for surface functional modification of graphene oxide. At the same time, the hydrophilicity of these oxygen-containing functional groups enables them to form a stable colloidal dispersion system in water, which is very beneficial to improve the dispersion of graphene oxide composites in water. Self-assembly process is a practical technology to integrate various nano-building modules into macromaterials with excellent properties. These self-assembled supramolecular materials have very good physical and chemical properties and are of great practical application value. As a new self-assembled nano-functional material, gel is a product obtained by gelation with appropriate organic solvent or water solvent, which has an ordered three-dimensional network structure. In this paper, graphene oxide was prepared by improved Hummers method, and then graphene oxide was prepared by ultrasonic peeling. Finally, GO-DETA hydrogel and GO-TETA hydrogel were designed and synthesized by self-assembly process. TEM,SEM,TGA, was used to prepare graphene oxide. The microstructure and properties of graphene oxide hydrogel were studied by AFM,XRD,FTIR,Raman et al. GO-DETA hydrogels and GO-TETA hydrogels were prepared by self-assembly of graphene oxide (GO) with diethylenetriamine (DETA) and triethylenetetramine (TETA) respectively. In this paper, three dyes, Rhodamine B (RhB), methylene blue (MB), Congo red (CR), and two heavy metal ions, Cu2 and Pb2, were adsorbed by hydrogel based on graphene oxide as adsorbents. The effects of the initial pH of the solution and the hydrogels of different mass concentrations on the adsorption performance were studied in detail, and the adsorption kinetics and thermodynamic experiments were also carried out in order to discuss the adsorption mechanism. The results show that the graphene oxide prepared by Hummers method has a two-dimensional lamellar structure and many folds on the surface. GO-DETA hydrogels and GO-TETA hydrogels were prepared by self-assembly of graphene oxide with diethylenetriamine and triethylenetetramine respectively. Through the analysis of adsorption kinetics and adsorption thermodynamics, it can be concluded that the adsorption of dye molecules in industrial wastewater by hydrogels based on graphene oxide is more consistent with the quasi-second-order kinetic model and the Freundlich isothermal adsorption model.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O648.17

【相似文献】