Superhydrophilic adsorptive nanofiber membranes for ultrafast and highly-efficient waterborne nanoplastic removal

Nanoplastics have emerged as hazardous contaminants of growing concern, presenting escalating risks to aquatic ecosystems and human health. While nanofiber membranes are compelling candidates for waterborne nanoplastic removal with high water permeation, nanoplastics have been proven hard to effectively separate due to the mismatch between the size removal threshold and nanoparticle size. Herein, we propose a synergistic adsorption-separation strategy that optimizes membrane structure and interfacial adsorption interactions via constructing entangled polyethylene oxide cross-linked network structures with polylactic polymer chains, which can capture polystyrene nanoplactics via multiple interfacial interactions (C-H⋯π/O-H⋯π interactions and hydrophobic interactions), amplify momentum attenuation and enable more than 99.99 % separation efficiency for the nanoplastics diameter larger than 150 nm. Simultaneously, polyethylene oxide (PEO) incorporation induced better hydrophilization and remarkable water permeation (60.4°→0° within 2.4 s), causing a permeance enhancement (3.21 ×10⁴ L m⁻² h⁻¹ bar⁻¹ under gravity-driven and 53.50 times higher than the original membrane). Besides the superior separation performance, the membrane maintains outstanding long-term separation stability, anti-fouling capability, and broad adaptability for sustainable NPs removal, outperforming state-of-the-art membranes. This breakthrough in design establishes a new example for treating volumes of nanoplastics in a short time, showing prominent treatment ability for multi-demand practical water and tremendous potential for water purification applications.