Bio-Inspired Synthesis and Photocatalytic Applications of α-Fe₂O₃@ZnO Nanobinary Using Laurus nobilis Leaf Extract: Efficient for Anionic and Cationic Dye Degradation With Reusability Studies

Abstract

This study investigates the sustainable synthesis and applications of α-Fe₂O₃@ZnO nanocomposites derived using Laurus nobilis leaf extract as a natural reducing agent, promoting eco-friendly material development for environmental remediation. XRD analysis confirmed the formation of the nanocomposite with a crystallite size of 21.48 nm, while SEM revealed a porous structure with uniformly distributed particles ranging from 20 to 50 nm. FTIR spectroscopy identified characteristic Fe-O and Zn-O bonds, ensuring the nanocomposite's purity. Optical analysis showed direct and indirect bandgap energies of 2.80 and 1.16 eV, respectively, highlighting its excellent optical properties. The nanocomposite demonstrated remarkable photocatalytic efficiency, achieving 96.3% degradation of Brilliant Cresyl Blue (BCB) dye and 95.88% degradation of Rose Bengal (RB) dye within 120 min under sunlight irradiation. The photocatalytic degradation followed first-order kinetics, with rate constants of 0.0241 min⁻¹ for BCB and 0.01875 min⁻¹ for RB. The nanocomposite exhibited excellent reusability, maintaining 93.5% degradation efficiency after five cycles, while XRD analysis confirmed its structural stability throughout repeated use. These results underscore the multifunctional potential of the green-synthesized α-Fe₂O₃@ZnO nanocomposite for dye-contaminated wastewater treatment, contributing to sustainable environmental technologies.