Electronic structure and site occupancy of lanthanide-doped (Sr, ca)3(Y, lu)2Ge3O12 garnets

A spectroscopic and first-principles study

Journal Article (2016)
Research Group
RST/Luminescence Materials
Copyright
© 2016 H. Luo, Lixin Ning, Yuanyuan Dong, A.J.J. bos, P. Dorenbos
To reference this document use:
https://doi.org/10.1021/acs.jpcc.6b09077
More Info
expand_more
Publication Year
2016
Language
English
Copyright
© 2016 H. Luo, Lixin Ning, Yuanyuan Dong, A.J.J. bos, P. Dorenbos
Research Group
RST/Luminescence Materials
Issue number
50
Volume number
120
Pages (from-to)
28743-28752
DOI:
https://doi.org/10.1021/acs.jpcc.6b09077
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

Photoluminescence excitation (PLE) and emission spectra (PL) of undoped (Sr, Ca)3(Y, Lu)2Ge3O12 as well as Eu3+- and Ce3+-doped samples have been investigated. The PL spectra show that Eu3+ enters into both dodecahedral (Ca, Sr) and octahedral (Y, Lu) sites. Ce3+ gives two broad excitation bands in the range of 200−450 nm. First-principle calculations for Ce3+ on both dodecahedral and octahedral sites provide sets of 5d excited level energies that are consistent with the experimental results. Then the vacuum referred binding energy diagrams for (Sr, Ca)3(Y, Lu)2Ge3O12 have been constructed with the lanthanide dopant energy levels by utilizing spectroscopic data. The Ce3+ 5d excited states are calculated by first-principles calculations. Thermoluminescence (TL) glow curves of (Ce3+, Sm3+)-codoped (Sr, Ca)3(Y, Lu)2Ge3O12 samples show a good agreement with the prediction of lanthanide trapping depths derived from the energy level diagram. Finally, the energy level diagram is used to explain the low thermal quenching temperature of Ce3+ and the absence of afterglow in (Sr, Ca)3(Y, Lu)2Ge3O12.

Files

Luo_et_al_J_Phys_Chem_C_170_20... (pdf)
(pdf | 2.18 Mb)
- Embargo expired in 25-11-2017
License info not available