Bio-inspired fabrication of Ag-ZnO nanoparticle decorated Nylon 11 nanofibers: Multifunctional membrane for environmental remediation

Abstract

Traditional wastewater treatment methods using nanoparticles encounter challenges with catalyst recovery. In this study, we fabricated a Nylon 11 nanofibrous membrane (NFM) via electrospinning and functionalized it with polydopamine to immobilize Ag-ZnO nanoparticles for photocatalytic degradation of organic pollutants. The Nylon 11 NFM was treated with a dopamine tris buffer solution for polydopamine (PDA) coating, which facilitated mussel-inspired attachment of the ZnO nanoparticles. These nanoparticles served as a nucleation site for the biomimetic nucleation of Ag-ZnONPs during the hydrothermal process. The synthesized composite membrane was characterized by various microscopic and spectroscopic techniques. The water contact angle decreased from 135° (Nylon 11 NFM) to 41° (PDA/Nylon 11 NFM) and the filtration efficiency improved 10 folds (from 15.92 Lm-2 hr-1 to 170.60 Lm-2hr-1) at ambient conditions. The Ag-ZnO/PDA/Nylon 11 NFM showed strong antimicrobial activity against different bacterial strains and excellent photocatalytic degradation for methyl orange with a rate constant of 0.0431 min-1, significantly surpassing other configurations. The membrane exhibited excellent stability, reusability and consistent photocatalytic efficiency over multiple cycles. It is easily recoverable from the reaction mixture, and suitable for repeated use, making it a promising candidate for environmental remediation due to its antibacterial properties, photocatalytic activity, enhanced filtration efficiency, and reusability.