High-efficiency, reusable electrokinetic filtration platform for high-Flux nanoplastic sequestration and self-powered operation

Abstract

The remediation of nanoplastic particles (NPPs) from aqueous environments remains a significant challenge, given their small dimensions, limited adsorption affinity, and high mobility. In this work, we report a reusable electrokinetic filtration platform that enables high-flux sequestration of NPPs along with self-sustained operation. The system employs magnesium oxide-coated porous nickel foam, achieving >99 % filtration efficiency (FE) for 50 nm polystyrene particles under a low-voltage (10 V) electric field, with a flux of 39.5 mL·cm−2·min−1. A theoretical framework was developed to describe the electrokinetic transport and surface adsorption, which demonstrated strong agreement with experimental observations. The model was further validated using cationic poly(vinyl alcohol)/poly(ethylene imine)–carbon dots, whose protonated amine groups exhibited a FE of 97.7 %. The platform enables regeneration by field reversal, consistently maintaining >93 % FE over 20 cycles. Integration with a triboelectric nanogenerator allows for off-grid operation while preserving >96 % FE. The system demonstrates stable performance in both tap and river water, reducing total dissolved and suspended solids to levels below WHO drinking water guidelines. This work offers an energy-independent, scalable solution for the remediation of NPPs in complex, real-world water matrices.