Characterization and application of the spinel CuCr2O4 synthesized by sol-gel method for sunset yellow photodegradation

This research attempted to synthesize a photocatalyst with a narrow bandgap and to investigate the possibility of using it to remove dyes from wastewater. The spinel CuCr2O4 (CCO) was selected as a topical catalyst as it showed interesting proprieties in previous studies. The catalyst CCO has been synthesized using the sol-gel method and used to degrade Sunset Yellow (SY) in a stirred reactor. Before starting, the phase was identified by X-ray diffraction (XRD) and Fourier transform infrared (FTIR). Rietveld structure refinement (RSR) and the maximum entropy method (MEM) were used to derive accurate electron-density distributions of CCO from X-ray diffraction results, as well as to study the crystal and electronic structures. An orthorhombic structural phase with space group Fddd was observed for CCO. The morphology of this spinel was investigated using a scanning electron micrograph (SEM) and transmission electron microscope (TEM). The optical properties were measured using Diffusion reflectance spectroscopy (DRS) and an optical gap band of 0.9 eV was determined. After characterization, the photocatalytic activity of CCO was investigated for SY degradation. The effect of pH, catalyst dose and initial concentration (C-o) on photocatalytic degradation was investigated. A degradation efficiency of 97% was achieved for 4 h under optimal conditions (pH 4, catalyst dose 0.8 g/L, C-o 10 ppm). [GRAPHICS] .

Automated summary

This research aimed to synthesize a photocatalyst with a narrow bandgap and investigate its potential for removing dyes from wastewater. The spinel CuCr2O4 (CCO) was chosen as the catalyst and synthesized through the sol-gel method. The synthesized CCO was characterized and tested for its photocatalytic activity, achieving a degradation efficiency of 97% for Sunset Yellow (SY) under optimal conditions.