Membrane fouling and wetting were two unsolved issues for membrane distillation (MD), fostered an enduring pursuit of well-designed superhydrophobic membrane. In this work, a novel hierarchically-structured superhydrophobic membrane was prepared by grafting octavinyl-polyhedral oligomeric silsesquioxane (OVPOSS) onto polyvinylidene fluoride (PVDF) membrane via UV-induced thiol-ene click reaction after the hydroxylation and sulfhydrylation pretreatment. The POSS/PVDF membrane exhibited high roughness and superhydrophobicity, and the pore structure was optimized with smaller size but centralized distribution. For the fabricated superhydrophobic membrane with low sliding angle (about 7.5°), the maintaining of Cassie-Baxter state and the “slip effect” significantly mitigated membrane fouling and wetting, due to the retardation of the liquid invasion into the gas-solid interface. It was found that scaling was the leading fouling for the commercial PVDF membrane, and the interaction between Ca²⁺ and carboxyl was the main organic fouling mechanism. While for the POSS/PVDF membrane, organic fouling via hydrophobic-hydrophobic interaction was the main membrane fouling and the scaling was significantly alleviated. The fabricated POSS/PVDF composite membrane had significant superiority over commercial PVDF membrane, which showed promising potential in challenging wastewater treatment. Additionally, this work also offered a new and facile method for superhydrophobic membrane fabrication.

膜污染和润湿是膜蒸馏 (MD) 的两个未解决的问题，促进了对精心设计的超疏水膜的持久追求。在这项工作中，在羟基化和巯基化预处理后，通过紫外线诱导的硫醇-烯点击反应将八乙烯基-多面体低聚倍半硅氧烷（OVPOSS）接枝到聚偏二氟乙烯（PVDF）膜上，制备了一种新型的分层结构的超疏水膜。POSS/PVDF膜表现出高粗糙度和超疏水性，优化了孔径较小但集中分布的孔结构。对于制造的具有低滑动角（约 7.5°）的超疏水膜，保持 Cassie-Baxter 状态和“滑动效应”显着减轻了膜的污染和润湿，由于液体侵入气固界面的延迟。发现结垢是商用 PVDF 膜的主要污垢，Ca 之间的相互作用²⁺和羧基是主要的有机污染机理。而对于 POSS/PVDF 膜，通过疏水-疏水相互作用产生的有机污染是主要的膜污染，结垢得到显着缓解。制造的 POSS/PVDF 复合膜比商用 PVDF 膜具有显着优势，在具有挑战性的废水处理中显示出广阔的潜力。此外，这项工作还为超疏水膜的制造提供了一种新的、简便的方法。