Electrospun nanofiber membranes for microplastic and nanoplastic removal from aquatic environments: a comprehensive...

The escalating contamination of aquatic ecosystems with microplastics (MPs) and nanoplastics (NPs) presents unprecedented environmental and health challenges worldwide. Electrospun nanofiber membranes have emerged as promising materials to address this crisis through their unique structural properties, tunable surface chemistry, and versatile removal mechanisms. This comprehensive review examines recent advances in electrospun fiber-based technologies for MP/NP removal, encompassing fundamental electrospinning principles, polymer selection strategies, surface modification approaches, and multi-functional designs. We critically analyze removal mechanisms, including size exclusion, electrostatic interactions, hydrophobic associations, and photocatalytic degradation, while evaluating performance metrics across diverse polymer systems ranging from synthetic polyacrylonitrile and poly(vinylidene fluoride) to bio-based cellulose and chitosan materials. Advanced functionalization strategies incorporating metal oxides, quaternary ammonium groups, and photocatalysts demonstrate remarkable synergistic effects, achieving removal efficiencies exceeding 99% for polystyrene particles of 0.1-25 µm in synthetic and doped natural water matrices under gravity-driven or low-pressure operation (0.04-0.7 bar). Reduced-but still > 85%-efficiencies are reported for sub-100 nm particles and for filtrations performed in real seawater and wastewater. The review addresses scalability challenges and environmental sustainability considerations aligned with the UN Sustainable Development Goals, including explicit linkage to SDG 6.3 wastewater-treatment targets, circular-economy principles, and the substantially lower energy footprint of gravity-driven electrospun membranes relative to reverse-osmosis systems. It also identifies critical research gaps requiring attention. Future directions emphasize integrated multi-functional platforms, green chemistry approaches, replacement of toxic solvents such as DMF by greener alternatives, melt electrospinning, and real-world validation to transition laboratory innovations toward practical implementation for safeguarding water quality and ecosystem health.