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Microplastics have been recognized as a critical threat to the aquatic ecosystem. Membrane separation technology displays great potential to address this issue, while current commonly‐used polymeric microfiltration membranes fall short of high separation efficiency due to their wide pore distribution. A perfectly simple strategy for homoporous membranes fabrication using commercial poly(vinylidene fluoride) (PVDF) was reported in this work, enabling precise removal of microplastics. In this strategy, hydrophilicity of dope solution was enhanced by adding proper amphiphilic surfactants initially, followed by a novelly‐inserted air exposure progress to gently provide water vapor. Both of the two easy steps induced a surface microscopic phase separation to achieve the growth of homopores. Furthermore, the as‐prepared PVDF membrane displayed high surface porosity and bi‐continuous cross‐section structure. As expected, a high rejection (over 97%) towards 500 nm polystyrene microparticles could be achieved along with satisfying water flux of 662 L m−2 h−1 bar−1, which was superior to most current membranes. This work provides not only a new and facile strategy for preparing homoporous membranes employing commercial polymers rather than rarely‐obtained block polymers, but a promising alternative for the efficient separation of aquatic microplastics. [ABSTRACT FROM AUTHOR]

The solubility behaviour of polysulfides in electrolyte solutions is a major bottleneck prior to the practical application of the lithium-sulfur battery. To address this issue, we fabricate a tannic acid/Fe III complex-coated polypropylene (PP) separator (TA/Fe III -PP separator) via a simple, fast, and green method. Benefiting from dual-confinement effects based on Lewis acid-base interactions between Fe III and polysulfides as well as the dipole-dipole interactions between rich phenol groups and polysulfides, the migration of polysulfides is effectively suppressed. Meanwhile, the porous structure of the PP separator is not destroyed by an additional coating layer. Thus, the TA/Fe III -PP separator can retain rapid lithium ion transport, eventually leading to a significant improvement in both the discharge capacity and rate performance of the corresponding lithium-sulfur cells. The cell with the TA/Fe III -PP separator presents a low capacity fade of 0.06% per cycle over 1000 cycles at 2.0 C, along with a high Coulombic efficiency of >97% over 300 cycles at 0.5 C. With respect to the one with the bare PP separator, the cell with the TA/Fe III -PP separator exhibits a 1.7-fold increase in the discharge capacity at 3.0 C. The proposed simple and economical approach shows great potential in constructing advanced separators to retard the shuttle effect of polysulfides for lithium-sulfur batteries.