Foller Tobias, Madauß Lukas, Ji Dali, Ren Xiaojun, De Silva K Kanishka H, Musso Tiziana, Yoshimura Masamichi, Lebius Henning, Benyagoub Abdenacer, Kumar Priyank V, Schleberger Marika, Joshi Rakesh
School of Materials Science and Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
Faculty for Physics and CENIDE, University of Duisburg-Essen, 47057 Duisburg, Germany.
Nano Lett. 2022 Jun 22;22(12):4941-4948. doi: 10.1021/acs.nanolett.2c01615. Epub 2022 Jun 10.
Angstrom-confined solvents in 2D laminates can travel through interlayer spacings, through gaps between adjacent sheets, and via in-plane pores. Among these, experimental access to investigate the mass transport through in-plane pores is lacking. Our experiments allow an understanding of this mass transport via the controlled variation of oxygen functionalities, size and density of in-plane pores in graphene oxide membranes. Contrary to expectations, our transport experiments show that higher in-plane pore densities may not necessarily lead to higher water permeability. We observed that membranes with a high in-plane pore density but a low amount of oxygen functionalities exhibit a complete blockage of water. However, when water-ethanol mixtures with a weaker hydrogen network are used, these membranes show an enhanced permeation. Our combined experimental and computational results suggest that the transport mechanism is governed by the attraction of the solvents toward the pores with functional groups and hindered by the strong hydrogen network of water formed under angstrom confinement.
二维层状材料中埃尺度受限的溶剂可以穿过层间距、相邻片层之间的间隙以及面内孔隙。其中，目前缺乏用于研究通过面内孔隙进行质量传输的实验方法。我们的实验通过可控地改变氧化石墨烯膜的氧官能团、面内孔隙的尺寸和密度，来帮助理解这种质量传输。与预期相反，我们的传输实验表明，较高的面内孔隙密度不一定会导致较高的水渗透率。我们观察到，面内孔隙密度高但氧官能团含量低的膜会完全阻止水的通过。然而，当使用氢键网络较弱的水 - 乙醇混合物时，这些膜的渗透性会增强。我们结合实验和计算的结果表明，传输机制受溶剂对带有官能团的孔隙的吸引力控制，并受到埃尺度限制下形成的水的强氢键网络的阻碍。
