Membrane distillation (MD) is promising desalination technology for hypersaline wastewater treatment. However, traditional MD membranes are subject to low vapor flux and mineral scaling. In this study, we report the fabrication of a composite membrane composed of polyvinylidene fluoride (PVDF) and metal azolate framework-4 (MAF-4) via electrospinning. The highly porous MAF-4 provides additional vapor transfer channels and better heat insulation, thereby significantly increasing the membrane flux compared to a bare electrospun PVDF membrane. The surface chemistry of the MAF-4 surface is further tailored with fluorinated functional groups through the coordination between the fluorinated molecule and the surface Zn atom. This surface modification changes the surface wettability of the MAF-4 and thus improves the membrane scaling resistance. This study demonstrates a universal approach for preparing high flux and scaling-resistant MD membranes. In addition, the tunable surface property of MAF-4 can also be utilized to design and fabricate other types of membrane surfaces by coordinating different functional molecules.

膜蒸馏（MD）是用于高盐废水处理的有前途的脱盐技术。然而，传统的 MD 膜受到低蒸汽通量和矿物结垢的影响。在这项研究中，我们报告了通过静电纺丝制备由聚偏二氟乙烯 (PVDF) 和金属唑酸盐框架 4 (MAF-4) 组成的复合膜。与裸电纺 PVDF 膜相比，高度多孔的 MAF-4 提供了额外的蒸汽传输通道和更好的隔热性，从而显着增加了膜通量。MAF-4 表面的表面化学通过氟化分子与表面 Zn 原子之间的配位进一步利用氟化官能团进行定制。这种表面改性改变了 MAF-4 的表面润湿性，从而提高了膜的抗结垢性。本研究展示了一种制备高通量和抗结垢 MD 膜的通用方法。此外，MAF-4的可调表面特性还可用于通过协调不同的功能分子来设计和制造其他类型的膜表面。