Natural cellulose-based multifunctional architecture for electrochemical removal and detection of nanoplastic

This study presents a novel cellulose-based composite electrode material, CMC/PEI/Co/PANI, designed for efficient electrochemical adsorption and in-situ detection of polystyrene nanoplastics. The material integrates a three-dimensional (3D) carboxymethyl cellulose/polyethyleneimine (CMC/PEI) network with two-dimensional (2D) cobalt hydroxide nanoplates and a polystyrene (PANI) conductive layer, addressing the limitations of poor conductivity and water solubility in pure CMC. Electrochemical adsorption experiments show that the composite achieves a removal rate of 77.91 % for 10 mg/L polystyrene nanoparticles within 3 h at 1.0 V, outperforming many reported materials. Meanwhile, electrochemical detection via cyclic voltammetry (CV) and differential pulse voltammetry (DPV) exhibits high sensitivity, achieving a detection sensitivity of 0.2866 μA/ppb·cm 2 , a correlation coefficient of 0.9917, and a detection limit of 0.63 ppb. Theoretical calculations reveal that the adsorption mechanism involves synergistic effects of electrostatic attraction, van der Waals forces, hydrogen bonding, π-π stacking, and hydrophobic interactions. These findings underscored the potential of CMC/PEI/Co/PANI composite in the removal and detection of nanoplastic contaminants within the context of environmental pollution management, offering a novel approach for controlling and mitigating nanoplastic contamination in the future.