Multifunctional CNF-AgNP Membranes for Enhanced Photocatalytic Water Purification

This study presents multifunctional cellulose nanofiber (CNF) membranes containing in situ-synthesized silver nanoparticles (AgNP) for the efficient removal of organic pollutants from water. These membranes combine the mechanical strength and adsorption capacity of nanocellulose with the plasmonic properties of AgNPs, which, under blue light irradiation, accelerate the photocatalytic degradation of contaminants such as dyes and antibiotics.

Performance tests demonstrated that CNF-AgNP membranes exhibit higher adsorption and also degradation behavior when irradiated by light. For that, kinetic studies were performed in a photoreactor with blue irradiation (457nm) and under dark conditions in the presence of CNF and CNF-AgNP membranes. The antibiotic Vancomycin was also investigated with the CNF-AgNP membrane under blue light exposure achieving almost 100% removal of vancomycin in 20 min.

In addition to pollutant removal, the membranes showed stability and reusability over multiple cycles while maintaining high efficiency and its integrity. Bacterial tests revealed that exposure of vancomycin to CNF-AgNP membranes under blue light reduced its antimicrobial activity.

These results emphasize the potential of CNF-AgNP membranes as a sustainable solution for water treatment, combining adsorption and plasmonic photocatalysis without the need for additional oxidative agents. This study paves the way for scaling up the application of these membranes, contributing to advanced water purification technologies.