Solvothermal synthesis of ZnTiO3 photocatalyst: Investigation of effect of pH and calcination temperature

In this study, zinc titanite nanoparticles were synthesized using the solvothermal method. The effects of pH and calcination temperature on the structures, morphology and photocatalytic activity of the resulting compounds were investigated.These nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), emission reflectance spectroscopy (DRS), X-ray energy dispersive spectroscopy (EDAX), Photoluminescence (PL) and UV-Vis spectroscopy.X-ray diffraction patterns confirmed the cubic pure ZnTiO3 structures synthesized at pH= 3 and calcination temperature of 700 ° C and hexagonal at pH=3 and pH=7 and calcination temperature of 800 ° C. Crystallinity was not visible in scanning electron microscope images. Also, full cubic and hexagonal structures of ZnTiO3 nanoparticles are easily visible in transmission electron microscopy images. In investigation photocatalytic results, Photocatalytic degradation kinetics data were evaluated by pseudo-first-order kinetics model. The efficiency of methylene blue dye degradation under visible light of the catalysts ZTO-10-900, ZTO-7-800, ZTO-3-700 was 95%, 83% and 78%, respectively. In ZTO-10-900 catalyst the presence of 423 and 527 nm bands in the photoluminescence emission spectra indicates the presence of crystalline defects in this compound and the major factor contributing to the higher efficiency in photocatalytic activity.