Nanofluidics and Ultrafiltration with track-etched Graphen-Polymer Composite Membranes

径迹蚀刻石墨烯聚合物复合膜的纳流体和超滤

• 批准号: 279028710
• 负责人: Professorin Dr. Marika Schleberger
• 金额: --
• 依托单位: Arbeitsgruppe Experimentelle Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/279028710?language=en
• 关键词: Nanofluidics; Ultrafiltration; track; etched; Graphen

Membranes can be used in a plethora of applications. As permeation-selective barrier they may serve as a separation membrane, for e.g., ultrafiltration, dialysis, water purification, or gas separation. In a more general context, they can also be used as a chemical, physical, or electrical barrier, e.g., in protective films, capacitors, or as sensors. For all these applications it is advantageous to make the membrane as thin as possible and at the same time as mechanically and chemically robust as possible. With respect to these criteria, graphene seems to represent the ideal material due to its mechanical strength and infinitesimal thickness of only 3 Å. Perfect graphene is impermeable for all gases and liquids and perforated graphene promises an unprecedented level of transport rates in filtering applications as the quasi two-dimensional selective membrane would exhibit negligible wall interactions. Thus, for membrane technologies novel composites based on graphene can offer significant improvements unachievable by conventional materials. The main goals of this proposal are the following: We aim to develop a process for the manufacturing of robust composites consisting of graphene and a polymer film, which will be processed further to produce ultrafiltration (UF) or nanofiltration (NF) membranes with relevance for technical separations, where the selective element is a single, artificially perforated layer of graphene. The performance of these UF and NF membranes will be assessed and the underlying mechanisms of manufacturing and separation processes will be elucidated. The perforation of the composite will be achieved by an established technology, i.e. the irradiation with swift heavy ions, enabling to control pore density and size in graphene. These pores will have a very narrow size distribution (isoporous) and their size can be selected in the range from 5 to 50 nm^2 thus offering a high degree of selectivity. By using another established technology known as track-etching, the selective barrier pores will be connected to larger pores in the supporting polymer film, yielding a unique composite UF or NF membrane. Functionalization of the pore entrance, in particular with charged groups, can be used to further increase selectivity so that even desalination of water may be feasible. As the transport through the 2D barrier layer is not hindered by wall interactions very low pressures are needed. It is therefore expected that the targeted membrane prototypes for UF or NF will outperform current materials by a factor of ~100 (in terms of higher fluxes at same selectivity) which would enable substantial energy savings. However, appropriate concepts for integration of such high flux membranes into modules are also absolutely necessary and therefore in this project micro-/nanofluidic separation systems based on graphene will be designed and investigated as first steps towards implementation of such radically novel membranes.

膜可以用在很多方面。作为渗透选择屏障，它们可以用作分离膜，例如，用于超滤、透析、水净化或气体分离。在更一般的情况下，它们还可以用作化学、物理或电气屏障，例如，在保护膜、电容器或传感器中。对于所有这些应用，有利的是使膜尽可能薄，同时尽可能地在机械和化学上坚固。就这些标准而言，石墨烯似乎代表了理想的材料，因为它的机械强度和只有3？的无限小厚度。完美的石墨烯对所有气体和液体都是不渗透的，而穿孔石墨烯有望在过滤应用中提供前所未有的传输速率，因为准二维选择性膜将显示出可以忽略不计的壁面相互作用。因此，对于膜技术来说，基于石墨烯的新型复合材料可以提供传统材料无法实现的显著改进。这一建议的主要目标如下：我们的目标是开发一种由石墨烯和聚合物薄膜组成的坚固复合材料的制造工艺，该复合材料将被进一步加工，以生产与技术分离相关的超滤(UF)或纳滤膜(NF)，其中选择性元件是单一的、人工穿孔的石墨烯。将评估这些超滤膜和纳滤膜的性能，并阐明制造和分离过程的基本机制。复合材料的穿孔将通过一种既定的技术实现，即用快速重离子照射，从而能够控制石墨烯中的孔密度和大小。这些孔的大小分布非常窄(等孔性)，其大小可以在5到50 nm^2的范围内选择，因此提供了高度的选择性。通过使用另一种被称为径迹蚀刻的成熟技术，选择性阻挡孔将连接到支持聚合物膜中的较大孔，从而产生独特的复合UF或纳滤膜。孔入口的功能化，特别是带有带电基团的功能化，可以用来进一步提高选择性，从而甚至可以实现水的淡化。由于通过2D势垒层的传输不受壁面相互作用的阻碍，因此需要非常低的压力。因此，预计用于超滤或纳滤的目标膜原型的性能将比目前的材料高出约100倍(在相同选择性下更高的通量)，这将大大节省能源。然而，将这种高通量膜集成到组件中的适当概念也是绝对必要的，因此在本项目中，将设计和研究基于石墨烯的微/纳米流体分离系统，作为实现这种全新膜的第一步。