Qi Benyu, He Xiaofan, Zeng Gaofeng, Pan Yichang, Li Guihua, Liu Guojuan, Zhang Yanfeng, Chen Wei, Sun Yuhan
CAS Key Laboratory of Low-carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Nat Commun. 2017 Oct 10;8(1):825. doi: 10.1038/s41467-017-00990-x.
To separate small molecules/species, it's crucial but still challenging to narrow the 2D-interspacing of graphene oxide (GO) membranes without damaging the membrane. Here the fast deposition of ultrathin, defect-free and robust GO layers is realized on porous stainless steel hollow fibers (PSSHFs) by a facile and practical electrophoresis deposition (ED) method. In this approach, oxygen-containing groups of GO are selectively reduced, leading to a controlled decrease of the 2D channels of stacked GO layers. The resultant ED-GO@PSSHF composite membranes featured a sharp cutoff between C2 (ethane and ethene) and C3 (propane and propene) hydrocarbons and exhibited nearly complete rejections for the smallest alcohol and ion in aqueous solutions. This demonstrates the versatility of GO based membranes for the precise separation of various types of mixtures. At the same time, a robust mechanical strength of the ED-GO@PSSHF membrane is also achieved due to the enhanced interaction at GO/support and GO/GO interfaces.Producing graphene oxide membranes with narrow channels is desirable for small molecule separations, but methods to narrow the 2D spacing typically result in membrane damage. Here the authors exploit electrophoresis-deposition to prepare GO membranes that are reduced in situ, leading to narrow and uniform 2D channels.
为了分离小分子/物质，在不损坏氧化石墨烯（GO）膜的情况下缩小其二维间距至关重要，但仍具有挑战性。在此，通过一种简便实用的电泳沉积（ED）方法，在多孔不锈钢中空纤维（PSSHFs）上实现了超薄、无缺陷且坚固的GO层的快速沉积。在这种方法中，GO的含氧基团被选择性还原，导致堆叠的GO层的二维通道可控减小。所得的ED-GO@PSSHF复合膜在C2（乙烷和乙烯）与C3（丙烷和丙烯）烃之间有明显的截止点，并且对水溶液中最小的醇和离子表现出几乎完全的截留率。这证明了基于GO的膜在精确分离各种类型混合物方面的多功能性。同时，由于GO/载体和GO/GO界面处相互作用的增强，ED-GO@PSSHF膜也具有强大的机械强度。制备具有狭窄通道的氧化石墨烯膜对于小分子分离是理想的，但缩小二维间距的方法通常会导致膜损坏。在此，作者利用电泳沉积来制备原位还原的GO膜，从而形成狭窄且均匀的二维通道。
