To enhance oil–water separation efficiency, it is urgent to synthesize novel membrane materials that exhibit high flux and high retention efficiency and excellent antisolvent property. Herein, a seeding–extension–bud protrusion procedure was developed to fabricate superhydrophobic separation membranes through UV-assisted grafting and covalent modification on a microporous polypropylene. The synthesized superhydrophobic membranes (PPN-HDI-TPFOS) exhibit a bud protrusion micro/nanostructure, which significantly increases the contact area between the membrane surface and the emulsion, as well as the collision among the emulsion droplets during the oil–water separation. This membrane shows high flux of up to 24 800 L m–2 h–1 for dichloromethane (DCM)/water immiscible oil–water mixtures and 6528 L m–2 h–1 for water-in-DCM emulsions, together with excellent water retention (>99%) as well as good antisolvent property. Moreover, it exhibits excellent retention rates (>98%) for other water-in-oil emulsions (kerosene, hexane, and cyclohexane). This work supplies a useful strategy to synthesize complex membrane with extremely high flux as well as high rejection rate.
Zhiang Zhang,Bing Han,Ruokun He,Shuaiqi Ren,Jiahao Fan,Wenzheng Han,Xumin Hou,Hesheng Wang,Zhuo-Chen Ma
Drawing inspiration from the doubly reentrant microstructures on springtail skins, surfaces exhibiting repellency to liquids with very low surface tension, are well developed. However, utilizing doubly reentrant microstructures for controllable wettability switching, especially for liquids with low surface tensions, still remains a challenge. Herein, a strategy is presented involving two-photon lithography-assisted molding to fabricate doubly reentrant soft microstructures (DRSMs) with real-time magnetic responsiveness. Owing to the high spatial resolution enabled by two-photon absorption and the dissolvable molding template, the 3D reentrant features are well preserved in the DRSMs based on the magnetic elastomer. Accordingly, the fabricated magnetic DRSMs exhibit switchable repellency for nearly all commonly used solvents within 1 s. Furthermore, the additional doubly reentrant micro-fence design surrounding the doubly reentrant micropillars allows the DRSMs to switch wettability even when fully immersed in liquids. These DRSMs demonstrate sufficient abilities for on-demand analyte enrichment and drug release. This work may not only serve as a design strategy to enhance the responsiveness of DRSMs but also significantly simplify the wetting switching system, which is highly attractive across various fields in biomedical and microelectronic applications.
危险品化学品经营许可证（带存储）