Energy transfer-based spectral properties of Tb-, Pr-, or Sm-codoped YAG : Ce nanocrystalline phosphors

초록

Tb(3+)-, Pr(3+)-, or Sm(3+)-cocloped YAG:Ce nanocrystalline phosphors were prepared using a modified polyol process. Possible tunability of Ce(3+)-related yellow emission in codoped YAG:Ce nanocrystalline systems was investigated. Dual emission of yellow and red spectral component with a single excitation wavelength was observed from YAG:Ce, Pr or YAG:Ce,Sm codoped systems via an energy transfer from Ce(3+) and Pr(3+) or Sm(3+) ion. It was also observed that the energy transfer event in YAG:Ce, Pr nanocrystalline phosphor occurs mutually between Ce(3+) <-> Pr(3+) while in YAG:Ce, Sm and YAG:Ce, Tb the energy transfer progresses one way. The detailed pathways for transferring an excitation energy are explained based on the energy level diagrams of respective Ce(3+), Pr(3+), Sm(3+), Tb(3+) ion. (C) 2008 Elsevier B.V. All rights reserved.

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