| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1524336 | Materials Chemistry and Physics | 2011 | 7 Pages |
Luminescent Ce3+-doped and Ce3+/Tb3+-codoped Y3Al5O12 powders and spray-coated films have been elaborated by the sol–gel technique. Their purity has been assessed by X-ray diffraction whereas X-ray Absorption Spectroscopy has evidenced the partial oxidation of Ce3+ into Ce4+ in samples containing or not Tb3+. Film thicknesses have been determined by profilometry. Powder and film morphology has been studied using Scanning Electron and Transmission Electron Microscopies, evidencing nanostructured well-densified phosphors. Scintillation properties of both kinds of samples have been investigated upon X-ray radiation and optimal cerium concentration has been determined for crystallized powders. Substitution of one part of yttrium ions by terbium ions in Y3Al5O12:Ce samples has entailed a significant enhancement of scintillation efficiency for both powders and films. These improvements will be discussed regarding in particular the changes in the X-ray absorption by photoelectric effect related to the matrix modification. In addition to this enhancement, emission maximum of co-doped samples is red-shifted to 544 nm, that matches more suitably with the optical photon detectors used in X-ray imaging.
► Synthesis of pure YAG:Ce3+ and YAG:Ce3+,Tb3+ powders made of clusterized nanoparticles via a sol–gel process. ► Elaboration of YAG:Ce3+ and YAG:Ce3+,Tb3+ coatings with thicknesses higher than 4 μm. ► Determination of an optimal concentration of cerium in powders upon X-ray radiation. ► Noticeable enhancement of scintillation properties by Tb3+ codoping for both powders and coatings.
