The sol-gel process was utilized for preparing fluoride-oxide composites as powders constituted of undoped or Eu3+ doped LiGdF4 nanocrystallites which are embedded in a silica network. Crystallization of the fluoride phase occurs after 700 °C heat treatment under inert atmosphere (Ar) using trifluoroacetic acid as in-situ fluorine source. Formation of well-crystallized and submicronic LiGdF4 crystallites were evidenced by X-ray diffraction and transmission electron microscopy respectively. Besides emission spectra as well as decay times of Eu3+ recorded from SiO2-LiGdF4-Eu3+ samples are similar to those obtained from single LiGdF4-Eu3+ fluoride emphasizing the formation of well-dispersed and pure fluoride nanocrystallites with a selective incorporation of Eu3+ ions inside this latter.
ASJC Scopus subject areas
- Materials Chemistry