Development and evaluation of a Zr-MOF/PVA nanofiber composite for efficient adsorption of malathion and carbofuran and antimicrobial control of aquatic pathogens

Abstract

Carbofuran and Malathion are widely used pesticides that pose serious environmental and health risks due to their persistence and high toxicity. In this study, a novel Zr/H₃Imdc/PVA nanofibrous composite was synthesized via microwave-assisted MOF formation followed by electrospinning and evaluated for simultaneous pesticide adsorption and antimicrobial activity. Characterization confirmed successful composite formation, with a high specific surface area and uniform nanofibrous morphology enriched with oxygen- and nitrogen-containing functional groups. The Zr/H₃Imdc-MOF exhibited a high specific surface area of 1560 m² g⁻¹, which increased to 1755 m² g⁻¹ upon incorporation into the PVA nanofibrous matrix, indicating preserved porosity and enhanced accessibility of active sites. Adsorption experiments showed maximum removal efficiencies of 94.9% for Malathion and 91% for Carbofuran using 0.04 g L⁻¹ adsorbent at neutral pH and 50 °C, with optimal contact times of 90 and 120 minutes, respectively, for an initial concentration of 400 mg L⁻¹. The high adsorption is attributed to the combined effect of Zr active sites, imidazole functional groups, and the nanofibrous PVA structure. Additionally, the composite exhibited notable antibacterial activity against five pathogenic aquatic bacterial strains, likely due to zirconium species, imidazole moieties, and enhanced surface interactions. These results demonstrate that the Zr/H₃Imdc/PVA nanofiber composite is a multifunctional material with promising potential for water purification, providing both pesticide removal and microbial control.