Organic solvent nanofiltration (OSN) is an energy-efficient alternative to distillation and evaporation for the separation of mixtures containing organic liquids. Laminar membranes using nanosheets as building blocks have great potential for OSN; however, a swelling of the interlayer spacing causes a severe decrease in the separation performance. Here, we present laminar HNb₃O₈-based composite membranes fabricated by vacuum filtration on an anodic aluminum oxide support for OSN applications. The laminar HNb₃O₈ membranes and composite (graphene oxide (GO) and HNb₃O₈) membranes were found to possess stable structures in various alcohols without severe swelling. As a result, the HNb₃O₈-based membranes showed higher dye rejections than the GO membrane. Among the HNb₃O₈-based membranes, the layered GO/HNb₃O₈ membrane had superior dye rejections in methanol (89.6% for Evans blue, 73.4% for acid red 265, and 43.4% for methyl orange) compared with the GO membranes. Alcohol permeation tests implied that the molecular diameter, rather than the solvent viscosity, was the dominant factor in the superior performance of the layered GO/HNb₃O₈ membrane. Molecular dynamics simulations suggest a stable GO/HNb₃O₈ interlayer ranging from around 1.165 to 1.333 nm, and a dense heterolayer formation at the interface between the HNb₃O₈ and GO layers. This heterolayer formation performs important roles in alcohol permeation and separation of organic dyes. Furthermore, the layered GO/HNb₃O₈ membrane showed stable permeation of a model photoresist waste liquid for 6 weeks and an excellent rejection of the photoresist waste, over 91%. We propose that laminar HNb₃O₈-based membranes have great potential for OSN applications.

有机溶剂纳滤 (OSN) 是一种节能的蒸馏和蒸发替代方法，用于分离含有机液体的混合物。使用纳米片作为构建块的层状膜具有巨大的 OSN 潜力；然而，层间距的膨胀会导致分离性能的严重下降。在这里，我们展示了层状 HNb ₃ O ₈基复合膜，通过真空过滤在阳极氧化铝载体上制造，用于 OSN 应用。发现层状HNb ₃ O ₈膜和复合（氧化石墨烯（GO）和HNb ₃ O ₈）膜在各种醇中具有稳定的结构而没有严重溶胀。因此，HNb基于₃ O ₈的膜显示出比 GO 膜更高的染料截留率。在基于 HNb ₃ O ₈的膜中，与 GO 相比，层状 GO/HNb ₃ O ₈膜在甲醇中具有优异的染料截留率（伊文思蓝为 89.6%，酸性红 265 为 73.4%，甲基橙为 43.4%）膜。酒精渗透测试表明，分子直径而不是溶剂粘度是层状 GO/HNb ₃ O ₈膜优异性能的主要因素。分子动力学模拟表明稳定的 GO/HNb ₃ O ₈1.165 到 1.333 nm 左右的夹层，以及在 HNb ₃ O ₈和 GO 层之间的界面处形成致密的异质层。这种杂层的形成在醇渗透和有机染料的分离中起着重要作用。此外，层状GO/HNb ₃ O ₈膜显示出6周内模型光刻胶废液的稳定渗透和光刻胶废液的优异阻隔，超过91%。我们提出基于层状 HNb ₃ O ₈的膜具有用于 OSN 应用的巨大潜力。