Eco-friendly synthesis and characterization of α-Fe2O3 nanoparticles and study of their photocatalytic activity for degradation of Congo red dye

In this work, α-Fe2O3 (hematite) nanoparticles were synthesized using Arabic gum (AG) as a biotemplate source by the sol-gel method. This method has many advantages such as low-cost, nontoxicity, simple work-up, high efficiency, compounds uniformity, and high efficiency. The α-Fe2O3 nanoparticles were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), UV-visible diffuse reflectance spectroscopy (DRS), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The results of XRD analysis revealed the formation of the rhombohedral phase of α-Fe2O3 nanoparticles with an average crystallite size of 19 nm. The TEM image illustrated the α-Fe2O3 nanoparticles with average particle size of 45-50 nm. The application of α-Fe2O3 nanoparticles as a photocatalyst was investigated for the degradation of the Congo red dye. The effects of photocatalyst dosage, initial dye concentration and visible light irradiation on dye degradation were assessed. The results demonstrated that the catalyst could degrade90% of the Congo red dye in 90 min. The α-Fe2O3 nanoparticles exhibited slight decrease in photocatalytic degradation of Congo red dye after four recycles.