Abstract: The Eu³⁺ ion doped SiO₂ aerogel film was prepared by a sol-gel process, and the luminescence and transitions of this aerogel film were investigated. The surface structure of the film was observed by AFM. Its microstructure was investigated
by XRD and IR. Its excitation, emission, absorption, and time-resolved spectra were measured. The luminescence properties were discussed. The radiative transition
probabilities of ⁵D₀ energy levels in Eu³⁺ ion were calculated by Judd-Ofelt theory. According to the time-resolved spectra, the nonradiative transition probabilities
and decay properties of ⁵D₁ were also studied. The results are not quite different to Eu³⁺ ion in silicate glass, but a fine thin film doped with rare earth ions
can be obtained by using a facile and low temperature method, and this film, having luminescent light glass qualities, can possess potential applications.

Key words: SiO₂ aerogel, doped-nanocrystals, rare-earth luminescent centers, time-resolved emission spectroscopy