We report the use of highly porous Janus membranes with unparalleled forward osmosis (FO) performance in terms of water flux and reverse salt flux. A porous Janus FO membrane, composed of a hydrophilic cellulose acetate layer and a hydrophobic polyvinylidene fluoride (PVDF) nanofiber layer, was fabricated by electrospinning. The resultant membrane exhibited outstanding FO performance, with a high water flux of 274.2 L m^–2 h^–1 and a low reverse salt flux of 1.65 g m^–2 h^–1 using 1 M NaCl draw solution. Different from the state-of-the-art thin film composite (TFC) membranes, the prepared Janus membrane demonstrates unparalleled FO performance via a nanofluidic diode model, whose high selectivity is determined by the air gap within the hydrophobic nanofiber layer that can effectively prevent the reverse salt diffusion. Wetting of the hydrophobic layer is the crucial issue in Janus FO membranes, which deserves further attention to extend the osmosis longevity.

中文翻译：

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具有无与伦比的正向渗透性能的Janus膜

我们报道了在水通量和反盐通量方面具有无与伦比的正向渗透（FO）性能的高多孔性Janus膜的使用。通过静电纺丝制备了由亲水性醋酸纤维素层和疏水性聚偏二氟乙烯（PVDF）纳米纤维层组成的多孔Janus FO膜。所得的膜表现出出色的FO性能，具有274.2 L m ^–2 h ^–1的高水通量和1.65 gm ^–2 h ^–1的低反向盐通量。使用1 M NaCl汲取溶液。与最新的薄膜复合（TFC）膜不同，所制备的Janus膜通过纳米流体二极管模型展示了无与伦比的FO性能，该模型的高选择性取决于疏水性纳米纤维层中的气隙，可以有效防止盐的反向扩散。疏水层的润湿是Janus FO膜的关键问题，值得进一步关注以延长渗透寿命。