化学修饰石墨烯膜的制备与性能研究

发布时间：2018-03-18 13:45

本文选题：石墨烯膜　切入点：强度　出处：《清华大学》2016年博士论文　论文类型：学位论文

【摘要】：石墨烯作为一种单原子层的二维晶体,拥有大量优异的性能。纳米尺度的石墨烯构筑的多维宏观组装体拓展了其在现实生产生活中的应用范围。其中,石墨烯二维组装膜材料在其应用领域中占据着重要的位置。本论文以超强、超韧、高电导率、多功能的化学修饰石墨烯膜材料的制备为研究重点,旨在简化制备流程,增强化学修饰石墨烯膜材料的综合性能,阐释其增强、增韧的内在机制。我们设计并合成了一种高分子聚丙烯酸-聚(3-苯硼酸丙烯酰胺)(PAPB0.2),以其作为氧化石墨烯(GO)水凝胶的凝胶化因子。同时我们建立了一种凝胶浇铸技术来制备超强、超韧、高导电的还原氧化石墨烯(rGO)/PAPB0.2膜。该复合膜的断裂强度、断裂伸长率和断裂韧性分别高达382±12 MPa、4.31±0.08%、7.50±0.40 MJ m~(~(-3))。更为重要的是,该方法制备的复合膜的电导率高达337±12 S cm~(-1),与本征的rGO膜相当(350±13 S cm~(-1))。这种简单的凝胶浇铸技术成本低廉、环境友好并且易于规模化生产任意形状、尺寸、厚度的化学修饰石墨烯膜材料。利用简便的酸诱导微结构控制的方法,在不需要外源高分子交联剂的条件下制备了机械性能增强的化学修饰石墨烯膜和化学修饰石墨烯纤维。该方法制备的膜强度高达447±29MPa,韧性达6.39±0.06 MJ m~(-3),远远高于大多数石墨烯基膜材料。更为重要的是,其热稳定性远远优于石墨烯/高分子复合膜。此外,该方法制备的一维纤维不仅具备极好的机械性能,还可作为耐火导线应用。我们提出的方法适合大批量制备超强、导电、热稳定的化学修饰石墨烯宏观组装体的制备。通过控制GO的化学结构结合温和的退火处理过程,我们制备了超强的本征GO膜和rGO膜。GO膜断裂强度高达453±17 MPa,并且能够在水中保持机械完整性。相应的化学还原的rGO膜的机械强度高达614±12 MPa,堪比AISI 304不锈钢(585 MPa)。与此同时rGO膜还具有超高的电导率(802±29 S cm~(-1))与热导率(524±36 W m~(-1) K~(-1))。利用片层尺寸大、结构更加完整的单/寡层氧化石墨烯作为构筑基元,通过简便的溶液挥发的方法制备了高导电的、溶液可加工的化学修饰石墨烯膜材料。该膜的电导率在碘掺杂后高达1440 S cm~(-1),断裂强度高达387±55 MPa。我们将此高电导率的化学修饰石墨烯膜作为轻质、可折叠的集流体应用于超级电容器中,展现了优异的速率性能。
[Abstract]:As a kind of two-dimensional crystal with single atomic layer, graphene has a lot of excellent properties. In this paper, the preparation of chemically modified graphene membrane materials with super strength, toughness, high conductivity and multifunction is the focus of the research, in order to simplify the preparation process. Enhance the comprehensive properties of chemically modified graphene film material, explain its reinforcement, The internal mechanism of toughening. We have designed and synthesized a kind of polymer polyacrylic acid-poly (3-phenylborate) acrylamide (PAPB _ (0.2)) as the gelation factor of graphene oxide (GOO) hydrogel, and we have established a gel casting technology to prepare super strong. The redox graphene oxide / PAPB 0.2 film is super tough and highly conductive. The fracture strength, elongation at break and fracture toughness of the composite film are as high as 382 卤12 MPA / 0.31 卤0.08 卤0.08 卤7.50 卤0.40 MJ / PAPB0.2 respectively. The conductivity of the composite membrane prepared by this method is as high as 337 卤12s / cm ~ (-1), which is equivalent to that of the intrinsic rGO film (350 卤13s / cm ~ (-1)). This simple gel casting technique is cheap, environmentally friendly and easy to be produced on a large scale in arbitrary shape and size. Chemically modified graphene film materials with thickness. A simple method for controlling the structure of graphene by acid induction. The chemically modified graphene film and chemically modified graphene fiber were prepared without external polymer crosslinking agent. The strength and toughness of the membrane prepared by this method were up to 447 卤29MPa and 6.39 卤0.06 MJ mf3, which was much higher than that of most of the films. Graphene based film materials. More importantly, Its thermal stability is much better than that of graphene / polymer composite membrane. In addition, the one-dimensional fiber prepared by this method not only has excellent mechanical properties, but also can be used as a fire-resistant conductor. Preparation of thermally stable chemically modified graphene macroassemblies. By controlling the chemical structure of go and the mild annealing process, We have prepared super strong intrinsic go and rGO films with breaking strength up to 453 卤17 MPa, and can maintain mechanical integrity in water. The corresponding chemically reduced rGO films have a mechanical strength of 614 卤12 MPA, which is comparable to that of AISI 304 stainless steel. At the same time, the rGO film also has a high conductivity of 802 卤29s / cm ~ (-1) and a thermal conductivity of 524 卤36W / m ~ (-1) ~ (-1). The highly conductive graphene oxide with more complete structure was prepared by a simple solution volatilization method as the building unit. Solution processable chemically modified graphene film material. The conductivity of the film is as high as 1440S cm ~ (-1) ~ (-1) after doping with iodine, and the breaking strength is as high as 387 卤55 MPA. The chemically modified graphene film with high conductivity is used as light weight. The foldable fluid collector is used in supercapacitors with excellent rate performance.
【学位授予单位】：清华大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TB383.2;TQ127.11

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