Nano zero-valent iron with a self-forming Co-catalytic surface for enhanced Fenton-like reactions.

Fenton reactions, commonly employed in environmental remediation, decompose H₂O₂ using Fe2⁺ to generate free radicals. However, the efficiency is often limited by the slow conversion of Fe³⁺ to Fe2⁺. In this study, we synthesize zero-valent iron nanoparticles (nZVI) via a green, plant extract-mediated reduction method, resulting in nZVI coated with a reductive polyphenolic layer that enhances Fe³⁺/Fe2⁺ cycling. Supported on bamboo-derived biochar (BBC) via in situ reduction, the nZVI showe improved dispersibility and recovery during catalytic processes. Characterizations by SEM, TEM, FTIR, XRD, and XPS together confirm the successful synthesis of the nZVI/BBC composite. We evaluate the catalytic performance by degrading Eriochrome Black T (EBT) dye in the presence of H₂O₂. Under optimal conditions (35 °C, pH 3), the nZVI/BBC catalyst achieves over 90% degradation of EBT within 10 min. The dual function of the surface-functionalized nZVI as both iron source and co-catalyst significantly improves the reaction efficiency, offering a promising approach for environmental remediation.