Synthesis and spectral characteristics of Sr2Y8(SiO4)6O2: Eu polycrystals |
| |
Authors: | M.G. Zuev A.M. Кarpov |
| |
Affiliation: | a Ural Federal University, 620002 Ekaterinburg, Russia b Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg, Russia c Institute of Metal Physics, Ural Branch of the Russian Academy of Sciences, 620041 Ekaterinburg, Russia |
| |
Abstract: | Spectral-luminescent characteristics of Sr2Y8(SiO4)6O2: Eu powder crystal phosphor with the apatite structure and high-intensity luminescence of Eu3+ ions have been studied. The charge state of europium in the samples has been characterized by means of X-ray L3-adsorption spectroscopy. It was established that Eu3+ forms two types of optical centers. Besides, luminescence of Eu2+ions was found. Reduction Eu3+→Eu2+ was considered, which may be due to vacancy formation in the 4f crystal lattice position and to negative charge transfer by this vacancy to two ions. Thus, in the silicate lattice there exist inhomogeneously distributed oxygen-deficient centers, which are responsible for nonradiative transfer of excitation energy to Eu3+ and Eu2+ ions. To study electron-vibrational interactions in the crystal phosphor samples, their IR and Raman spectra were examined. In the luminescence spectrum of Eu2+, a series of low-intensity bands caused by interaction of the 4f65d state of Eu2+ with silicate lattice vibrations was observed. |
| |
Keywords: | Yttrium silicate X-ray diffraction Vibrational spectra Luminescence Eu2+ Eu3+ Oxygen vacancies |
本文献已被 ScienceDirect 等数据库收录! |
|