Document Type : Research Paper
Chemistry, Iran University of Science and Technology, Tehran, Iran
Morphology and synergistic effect are two important factors that greatly influence the physical and chemical properties of materials. We report the magnetic octahedral NiFe2O4 (NFO) crystals synthesized by simple multistep approach. The octahedral morphology of NFO was confirmed by using Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDX). Vibrating sample magnetometer (VSM) and Differential reflectance spectroscopy (DRS) results show that NFO crystals exhibit a better ferromagnetic behavior than previous reports, with Ms value of 93.43 emu.g-1 and band gap of 2.40 eV, respectively, making NFO crystals a suitable candidate for photocatalytic degradation of Congo Red (CR) by visible-light irradiation. The effect of reaction time, pH, initial CR concentrations, and dosage catalyst along with the mechanism and adsorption kinetic were investigated. The regression equation was found in a good agreement with the pseudo-first-order kinetic model(r = - dC/dt = kKC/1+K ). Results demonstrated that NFO photo catalyst with its special structure, and more active sites is an excellent efficiency for the removal of CR.