Effect of annealing temperature and doping concentrations on structure and optical properties of Eu3+-doped TiO2 nanomaterials

In this study, we successfully synthesized europium-doped TiO2 (TiO2 :Eu3+) nanomaterials (NMs) with crystalline sizes ranging from 6.5 to 71.7 nm through a sol-gel method. Analysis of X-ray diffraction (XRD) patterns and ultraviolet-visible (UV-Vis) spectra indicates that the substitution of smaller-sized Ti4+ ions (0.745 Å) by largersized Eu3+ ions (0.947 Å) was more efficient at higher doping concentrations and annealing temperatures.