Analysis of optical and structural properties of Ti-doped ZnO nanoparticles synthesized by co-precipitation method

In this study, we used the co-precipitation method to synthesize Ti-doped ZnO nanoparticles having different Ti contents. We then used energy dispersive X-ray spectroscopy to perform an elemental analysis, which revealed that the Ti content varied in its atomic percentages from 5 at.%, 7 at.%, and 12 at.% to 16 at.%. We characterized the structural properties of the prepared samples using X-ray diffraction (XRD) spectroscopy and found Ti-doped ZnO to have an anatase structure in which the lattice parameters a = b and c decrease from 3.251 and 5.213 Å to 3.254 and 5.203 Å, respectively, when the Ti content increased from 5 at.% to 16 at.%. We also found the grain size of Fe-doped TiO₂ to decrease from 12 nm to 10 nm with increasing Ti content. We characterized the molecular vibration of the samples using Fourier transform-infrared spectroscopy (FT-IR) and the optical properties using UV-Vis diffuse reflectance spectroscopy. The results show the band-gap energy of Ti-doped ZnO to decrease from 3.20 eV to 3.12 eV. We tested the photocatalytic activity of Ti-doped ZnO in the degradation of methylene blue from the aqueous solution under UV light irradiation and found the photocatalyst Ti-doped ZnO to have good degradation ability, with a degradation percentage of approximately 80 %.