Luminescence properties and energy transfer of Ce3+/Eu3+ doped GSBA glass

Through the method of conventional high-temperature melting, Ce ³⁺/Eu ³⁺doped GeO ₂-SiO ₂-BaO-Al ₂O ₃ (GSBA) glasses were fabricated. Photoluminescence spectrum, Fourier transform infrared spectroscopy, absorption spectrum, fluorescence attenuation time and CIE color coordinates were tested to investigate the optical properties and structure of glass. Using the formula of Dexter`s energy transfer, the energy transfer from Ce <sup>3+</sup> to Eu <sup>3+</sup> was studied. The band gap as well as spacing between rare earth ion were obtained by theoretical calculation. The results show that the optimal cerium ion concentration of the Ce <sup>3+</sup> doped and Ce <sup>3+</sup>/Eu <sup>3+</sup> co-doped GSBA glass was consistent, which is 0.3 mol%. For the samples only doped with Ce <sup>3+</sup>, there has no significant changes of glass structure with increasing Ce <sup>3+</sup> concentration, and multiple ligands of [GeO <sub>4</sub>], [GeO <sub>6</sub>], [SiO <sub>4</sub>], [SiO <sub>4</sub>]&[G eO <sub>4</sub>], [AlO <sub>4</sub>] and [AlO <sub>6</sub>] co-existed in glass structure. It is proved that there is energy transfer from Ce <sup>3+</sup> to Eu <sup>3+</sup> and the form of energy transmission is electric quadrupole-quadrupole transfer. What`s noteworthy is that in Ce ³⁺/Eu ³⁺ double-doped glass, the prepared glass material can emit white light through changing the doped concentration of Eu ³⁺ ion, and color temperature is all below 3300 K, which proves the application potential of Ce ³⁺/Eu ³⁺ co-doped germanosilicate glass in the field of warm white LED.