Photoluminescent properties of LaF3:Eu3+ and GdF3:Eu3+ nanoparticles prepared by co-precipitation method

LaF3:Eu3+ and GdF3:Eu3+ nanoparticles were prepared by a co-precipitation method in the presence of the chelating agent, citric acid. The structural properties of the products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average crystallite size was estimated from the full-width at half-maximum (FWHM) of the diffraction peaks by the Scherrer equation. The sizes of the nanoparticles were 12 nm for LaF3:Eu3+ and 17 nm for GdF3:Eu3+. The luminescent properties of the nanoparticles were investigated by excitation and emission spectra. Energy transfer from Gd3+ to Eu3+ was observed.