Green synthesis and characterization of spinel ZnMn2O4 nanoparticles by tragacanth gel and studies of its photocatalytic activity for degradation of Congo red dye under visible light irradiation

In this work, ZnMn2O4 spinel nanoparticles was successfully synthesized by tragacanth gel through the easy and inexpensive novel sol-gel method. This technique has many strong points such as facile, economical, non-toxic and quickness in comparison with other methods. The magnesium manganite nanoparticles characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transforms infrared spectroscopy (FTIR), and percent of dye degradation which was followed by UV–Visible spectroscopy. The XRD pattern confirmed the formation of spinel tetragonal structure of ZnMn2O4 nanoparticles with crystallite size of 14 nm. The ZnMn2O4 NPs expressed high photocatalytic activity for degradation of Congo red dye at room temperature in aqueous solution so that 96% of Congo red was degraded in 15 min.