PDF(Pubmed)
Abstract：
Graphene oxide (GO) with its atomic thickness and abundant functional groups holds great potential in molecular-scale membrane separation. However, constructing high-speed and highly selective water transport channels within GO membranes remains a key challenge. Herein, sulfonato calix[n]arenes (SCn) molecules with a cavity structure, hydrophilic entrance, and hydrophobic wall were incorporated into GO interlayer channels through a layer-by-layer assembly approach to facilitate water permeation in a water/ethanol separation process. The hydrophilic entrance enables preferential access of water molecules to the cavity over ethanol molecules, while the high hydrophobicity of the cavity wall confers low resistance for water diffusion. After incorporating SCn molecules, the membrane shows a remarkable increase in the water/ethanol separation factor from 732 to 1260, while the permeate flux also increases by about 50%. In addition, the strong electrostatic interactions between the building blocks endow the membrane with excellent swelling resistance even under a high water content. This work provides an effective strategy of constructing high-efficiency water transport channels in membrane.
摘要：
氧化石墨烯（GO）具有原子厚度和丰富的官能团，在分子尺度膜分离中具有巨大的潜力。然而,在GO膜内构建高速和高选择性的水运输通道仍然是一个关键挑战。在这里，具有空腔结构的磺基杯[n]芳烃（SCn）分子，亲水入口,和疏水性壁通过逐层组装方法结合到GO层间通道中以促进水/乙醇分离过程中的水渗透。亲水入口使得水分子优先进入空腔而不是乙醇分子。而空腔壁的高疏水性赋予水扩散阻力低。掺入SCn分子后，膜显示水/乙醇分离因子从732到1260的显著增加,而渗透物通量也增加约50%。此外,构建块之间的强静电相互作用赋予膜即使在高含水量下也具有优异的抗溶胀性。这项工作提供了一种有效的策略，在膜中构建高效的水传输通道。
