High-Performance Gas Separation Membranes by Guided-Assembly of Graphene-based Nanocomposites

通过石墨烯基纳米复合材料的引导组装实现高性能气体分离膜

基本信息

批准号：
19F19367
负责人：
Sivaniah Easan
金额：
$ 1.41万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for JSPS Fellows
财政年份：
2019
资助国家：
日本
起止时间：
2019-11-08 至 2022-03-31
项目状态：
已结题

项目摘要

Our research achievements in this project are threefold. First, we have found that the GO-polycation composites coagulate too fast to give uniform slurries and, thus, defect-free gas separation membranes. At high GO-polycation loadings (high concentrations), we could obtain conformal coatings with rod/blade-coating methods. But the resulting membranes became too thick but were still often defective because of fast aggregation. We could produce smoother coatings using non-polyelectrolytes (such as hydrogen-bondable polymers) but still observed only low hydrogen selectivity. However, when we used positively charged nanoparticles and vacuum filtration, we achieved conformal and defect-free membranes, yielding selectivities up to 150 and permeabilities up to around 4000 GPU. Based on the experiments made with polymer-free nanosheet dispersions, we also found that vacuum filtration can be used for compacting membranes that are prepared by other coating methods such as spray-coating. Overall, this collaborative research resulted in the establishment of four fundamental notions: (1) Electrostatic interactions are highly effective in stabilizing GO-based membranes; (2) guided-assembly methods (such as vacuum-assisted filtration and vacuum-spray-coating) should be optimized for achieving defect-free membranes; (3) composite membranes should be polymer-free or rich in nanosheets for developing defect-free membranes with high hydrogen selectivity.

我们在这个项目中的研究成果有三个方面。首先，我们发现 GO-聚阳离子复合材料凝结速度太快，无法形成均匀的浆料，从而无法形成无缺陷的气体分离膜。在高 GO 聚阳离子负载量（高浓度）下，我们可以通过棒/刀片涂覆方法获得保形涂层。但所得膜变得太厚，但由于快速聚集，仍然经常存在缺陷。我们可以使用非聚电解质（例如氢键聚合物）生产更光滑的涂层，但仍然观察到氢选择性较低。然而，当我们使用带正电的纳米颗粒和真空过滤时，我们获得了保形且无缺陷的膜，选择性高达 150，渗透率高达 4000 GPU 左右。基于无聚合物纳米片分散体的实验，我们还发现真空过滤可用于压实通过其他涂覆方法（例如喷涂）制备的膜。总的来说，这项合作研究建立了四个基本概念：（1）静电相互作用对于稳定 GO 膜非常有效； (2) 应优化引导组装方法（例如真空辅助过滤和真空喷涂）以获得无缺陷的膜； (3)复合膜应不含聚合物或富含纳米片，以开发具有高氢选择性的无缺陷膜。