Photocatalytic Removal of Crystal Violet Dye Utilizing Greenly Synthesized Iron Oxide Nanoparticles

Abstract

The presence of synthetic industrial dyes in the environment poses significant risks to aquatic ecosystems, human health, and economies. This study aims to synthesize iron oxide nanoparticles (IONPs) using a green method, analyze them using physicochemical techniques, and examine the effectiveness with which they photocatalytically degrade crystal violet dye in sunlight. Fourier transform infrared spectroscopy (FTIR) analysis revealed that the biogenic IONPs showed a UV peak at a wavelength of 241 nm, with functional groups including phenols, alkynes, and alkenes. X-ray diffraction (XRD) analysis confirmed the amorphous nature of the bioinspired IONPs. The mean diameter of the biogenic IONPs was 49.63 ± 9.23 nm, and they had a surface charge of −5.69 mV. The efficiency with which the synthesized IONPs removed the crystal violet dye was evaluated under dark and sunlight conditions. The removal efficiency was found to be concentration and time dependent, with a peak removal percentage of 99.23% being achieved when the IONPs were exposed to sunlight for 210 min. The biogenic IONPs also demonstrated antioxidant activity, with a relative IC50 value of 64.31 µg/mL. In conclusion, biogenic IONPs offer a viable and environmentally friendly approach for eradicating industrial synthetic dyes and remediating contaminated environments and aquatic ecosystems.

Keywords

• green synthesis
• <i>Camellia sinensis</i>
• characterization
• dye removal
• antioxidant