Synthesis and Characterization of Nano CoFe2O4 Prepared by Sol-Gel Auto-Combustion with Ultrasonic Irradiation and Evaluation of Photocatalytic Removal and Degradation Kinetic of Reactive Red 195

Abstract

A combination of sol-gel auto-combustion and ultrasonic irradiation methodswere developed for fabrication of CoFe2O4nanoparticles using aqueous solution of Co(NO3)2.6H2O and Fe(NO3)3.9H2O with glycine as chelating agent under nitrogen atmosphere. CoFe2O4 nano-particles werecoated on glass by Doctor Blade method. The precursor powders were analyzed by thermogravimetry (TG) and differential thermogravimetry (DTG). The structural, optical and the chemical features of the nano-particles have been studied by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV–Vis diffuse reflectance spectroscopy (DRS).The results of TG-DTG indicated that the CoFe2O4nano-particles have a very good thermal stability. Powder XRD analysis confirmed formation of CoFe2O4 spinel phase. The morphological and optical properties of the cobalt ferrite were found to be depended on ultrasonic irradiation. Nanoparticles prepared with ultrasonic irradiation have diameter of about 46 nmwith spherical morphology and narrow size distribution and nanoparticles prepared without ultrasonic irradiation is about 57 nm. The photocatalytic activity of the immobilizedcobalt ferrite nanocomposite was studied on Reactive Red 195 (RR195) as an azo textile dye used textile industries and the results showed about 74% degradation in less than 2 h. The photocatalytic activity of CoFe2O4nanoparticles is attributed to band gap energy and small particle size. The coated cobalt ferrite nanocomposite with a reproducible photocatalytic activity was well separable from water media by removing the glass coated with thin film and acted as a promising catalyst for the remediation of textile wastewater. Degradation of Reactive Red 195 by cobalt ferrite nanocomposite coated on glass follows second order rate kinetic.