The development of a stable structure separation membrane with adaptive switching wettability has positive significance for the expansion of membrane applications, especially in complex processing scenarios. Herein, a kind of core-shell cellulose acetate/silicon dioxide (CA/SiO) hybrid nanofiber membrane with a semi-interpenetrating structure and switching wettability surface property was prepared via electrospinning process and subsequently in-situ hydrolysis, which integrated a superamphiphilicity SiO shell onto the porous CA nanofibers core to form an anchor embedding structure by vacuum forcing the silica precursor into the pores of CA nanofibers. The obtained CA/SiO hybrid nanofiber membrane exhibited superamphiphilicity in air with adaptive switching wettability, appearing non-stick to oil underwater or to water underoil, corresponded to superoleophobicity underwater and superhydrophobicity underoil, respectively. The CA/SiO hybrid nanofiber membrane with the hydrolysis time of 5 h demonstrated excellent properties. It achieved permeation fluxes of 19771 and 9104 L/m·h with a separation efficiency exceeding 99.99% for immiscible light/heavy oil/water mixtures when pre-wetted by water and oil and subjected to gravity. Moreover, the semi-interpenetrating structure of SiO nanoparticles to CA nanofibers ensured the structural stability of the CA/SiO hybrid nanofiber membranes, which endowed it with excellent reusable performance.

中文翻译：

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具有半互穿结构和切换润湿性的CA/SiO2杂化纳米纤维膜的结构设计


开发具有自适应切换润湿性的稳定结构分离膜对于扩大膜应用特别是在复杂的处理场景中具有积极意义。本文通过静电纺丝工艺和随后的原位水解制备了一种具有半互穿结构和可切换润湿性表面性质的核壳醋酸纤维素/二氧化硅（CA/SiO）杂化纳米纤维膜，该膜集成了超两亲性SiO壳通过真空迫使二氧化硅前体进入CA纳米纤维的孔中，将其附着到多孔CA纳米纤维芯上，形成锚定嵌入结构。所得CA/SiO杂化纳米纤维膜在空气中表现出超两亲性，具有自适应切换润湿性，对水下油或油下水不粘，分别对应于水下超疏油性和油下超疏水性。水解时间为5 h的CA/SiO杂化纳米纤维膜表现出优异的性能。当水和油预润湿并受到重力作用时，它的渗透通量分别为 19771 和 9104 L/m·h，对于不混溶的轻/重油/水混合物的分离效率超过 99.99%。此外，SiO纳米颗粒与CA纳米纤维的半互穿结构保证了CA/SiO杂化纳米纤维膜的结构稳定性，使其具有优异的可重复使用性能。