Investigating the Photocatalytic Degradation of Amaranth Dye in Water Environment using Visible Light‐Activated Fe‐Doped ZnO Nanoparticles

Abstract

These days, the removal of dissolved organics from industrial waste water is a foremost challenge to the scientific community to attain the conservation of the aqueous ecosystem. The present work emphasizes the photocatalytic degradation of industrial dye, that is, Amaranth using Fe‐doped ZnO (Fe‐ZnO) nanoparticles. The formation of wurtzite phase bare ZnO and Fe‐ZnO materials fabricated by the solvothermal route is confirmed by XRD and Fourier‐transform infrared spectroscopy, whereas the scanning electron microscopy morphological investigations reveal the formation of coral‐like to granular particles. The bandgap energies of the synthesized materials are observed to be shifted to the blue region on gradual Fe doping, indicating the suitability of the material for photocatalysis. The photocatalytic activity of the as‐synthesized ZnO and Fe‐ZnO materials is evaluated under sunlight and mercury lamp light, wherein the 6% Fe‐ZnO material shows more than 98% degradation of Amaranth dye within 80 min in sunlight. The kinetic studies shows pseudo‐first‐order degradation reaction with a rate constant of 0.0114 min−1 in sunlight. The effects of catalyst loading, light source, and stability of the photocatalyst are also explored along with a proposed photogenerated free radical‐based dye degradation mechanism.