Effective modification strategies contribute to high adsorption capacity, separation efficiency and anti-fouling properties of ion-imprinted membranes. The design of a homogeneous and hydrophilic interlayer between the substrate membrane and ion-imprinted layer is crucial factor for the excellent performance of ion-imprinted membranes. In this study, a novel multilayered interlayer (SiO₂@SP-PDA) was developed and uniformly coated on the substrate surface (PVDF membrane). The polydopamine (PDA) prepared via oxidation of sodium periodate (SP-PDA) increases the uniformity of SiO₂@SP-PDA modification, which reduces the agglomeration of the ion-imprinted layer, and thereby boosts the adsorption capacity to 231.77 mg·g⁻¹. The prepared ion-imprinted membrane (SiO₂@SP-PDA-IIM) exhibits a favorable anti-fouling property due to the incremental hydrophilicity and the presence of SiO₂ nano interlayer. Based on the XDLVO theory, it can be deduced that the SiO₂ modification increases the membrane surface electron donor tension (γ⁻), which plays an essential role in enhancing the anti-fouling property of SiO₂@SP-PDA-IIM. In this paper, the design of multilayered structure is of great significance to make the ion-imprinted membrane be a potential candidate for Li⁺ efficient separation in natural water.

有效的改性策略有助于离子印迹膜的高吸附容量、分离效率和防污性能。在基底膜和离子印迹层之间设计均匀的亲水性中间层是离子印迹膜具有优异性能的关键因素。在这项研究中，开发了一种新型多层中间层（SiO ₂ @SP-PDA），并将其均匀地涂覆在基材表面（PVDF 膜）上。高碘酸钠（SP-PDA）氧化制备的聚多巴胺（PDA）提高了SiO ₂ @SP-PDA改性的均匀性，减少了离子印迹层的团聚，从而将吸附量提高到231.77 mg·g ^-1。制备的离子印迹膜（SiO_{2 @SP-PDA-IIM) 由于增加的亲水性和 SiO 2}纳米夹层的存在而表现出良好的防污性能。基于XDLVO理论，可以推断SiO ₂改性增加了膜表面电子供体张力（γ ^{- ），这对提高SiO} ₂ @SP-PDA-IIM的防污性能起着至关重要的作用。本文的多层结构设计对于使离子印迹膜成为天然水中Li ^{+高效分离的潜在候选者具有重要意义。}