分级多孔结构石墨烯/金属氧化物纳米复合材料的可控制备及吸附机制研究

The design and synthesis of graphene-based nanocomposites driven by target contaminats is the key to the application of graphene materials in the adsorption field. The project is aimed at the removal of the pharmaceuticals and personal care products that exist in the environment widely. By using the graphene oxide and metal salt as the precursor, novel hierarchical graphene/metal oxide nanocomposites with porous structure will be fabricated and researched. The effect of synthetic methods and reaction conditions on the chemical constituents and structure, as well as morphology of the composites will be revealed. Various modern instrument analytical technique (XRD, TEM, FTIR, and XPS, etc) will be used to study the mechanisms of the formation of hierarchical graphene/metal oxide nanocomposites with porous structure, and the absorption thermodynamics, adsorption kinetics, surface morphology, and adsorption mechanism of pollutants on the nanocomposites will also be studied. The relationship between the chemical constituents, structures and morphology of nanocompsoties with the absoption properties of pollutants on the graphene/metal oxide nanocomposites will be clarified. The binary synergistic enhancement adsorption mechanism of graphene and metal oxides will also be revealed. The implementation of the subject to provide a theoretical basis and technical support for the design and preparation of novel pollutant adsorbent.

以目标污染物驱动设计和合成石墨烯基复合材料是解决石墨烯材料在吸附领域应用的关键。本项目以去除广泛存在的药品和个人护理用品污染物为目标，采用氧化石墨烯和金属盐为原料，拟设计具有分级多孔结构的石墨烯/金属氧化物纳米复合材料；探索合成方法和反应条件对复合材料的组成、结构以及形貌的影响规律；通过XRD、TEM、FTIR、XPS等手段研究复合材料的合成机理以及污染物在复合材料表面上的吸附热力学、吸附动力学、吸附的表面形态以及吸附机理；阐明复合材料的组成、结构和形貌与复合材料吸附性能的构效关系，揭示复合材料中石墨烯与金属氧化物间的协同作用机理。课题的实施为设计和合成新型高效去除污染物的吸附材料提供理论依据和技术支持。

本课题围绕水体中重金属离子和新兴污染物PPCPs的高效去除，以石墨烯等碳基复合材料为研究对象，制备了5种新型高效净水材料，它们分别是石墨烯基氧化锰、氧化铁、铁酸锌多孔纳米复合材料、磁性纳米碳/金属氧化物多孔复合材料、分级多孔碳材料、分级多孔UiO-66及其衍生物、碳/二氧化钛纳米多孔复合材料；研究了它们对水体中重金属Pb2+以及阿特拉津、卡马西平、双酚A、四环素、诺氟沙星和对硝基苯酚等污染物的吸附去除性能。通过改变制备方法、调控试剂用量和反应温度等合成参数，对上述所制备的分级多孔结构纳米复合材料进行了优化，掌握了调节该纳米复合材料孔结构、组分和表面微化学环境的关键技术。采用现代仪器分析方法和模拟计算系统阐明了上述目标污染物在所制备的分级多孔结构纳米复合材料表面发生吸附的吸附作用位点和作用机制；其中首次采用TEM和XPS观察并揭示了纳米ZnO基于离子交换过程去除Pb2+的吸附机制。此外，考虑实际水化学条件的影响，开展了模拟废水中各种干扰离子和腐殖酸等对目标污染物在所制备的分级多孔纳米吸附剂材料表面吸附的影响，并同时开展了吸附材料的再生及循环利用性能的研究。取得了一系列创新性研究成果，为开发新型高效净水材料提供了理论基础。