Spectroscopic analysis of Eu{sup 3+} -and Eu{sup 3+}:Yb{sup 3+}-doped yttrium silicate crystalline powders prepared by combustion synthesis

Journal Article · Fri Oct 15 00:00:00 EDT 2010 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3489992· OSTI ID:21476511

Rakov, Nikifor ^[1]; Amaral, Dayanne F; Guimaraes, Renato B; Maciel, Glauco S ^[2]

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1. PG-Ciencia dos Materiais, Universidade Federal do Vale do Sao Francisco, 48902-300 Juazeiro, BA (Brazil)
2. Instituto de Fisica, Universidade Federal Fluminense, 24210-346 Niteroi, RJ (Brazil)

Yttrium silicate powders doped with Eu{sup 3+} and codoped with Eu{sup 3+} and Yb{sup 3+} were prepared by combustion synthesis. The x-ray powder diffraction data showed the presence of Y{sub 2}SiO{sub 5} and Y{sub 2}Si{sub 2}O{sub 7} crystalline phases. Singly doped (1 wt %) sample illuminated with ultraviolet light ({lambda}=256 nm) showed the characteristic red luminescence corresponding to {sup 5}D{sub 0}{yields}{sup 7}F{sub J} transitions of Eu{sup 3+}. The Judd-Ofelt intensity parameters were calculated from experimental data and the radiative and nonradiative relaxation rates were estimated. The results showed that the nonradiative relaxation rate is smaller in yttrium silicate compared to yttrium oxide powder, a reference material, prepared under similar conditions. Codoped samples were exposed to near-infrared laser excitation ({lambda}=975 nm) and the red luminescence of Eu{sup 3+} was also observed. In this case, the luminescence is achieved due to a cooperative upconversion (CUC) process involving energy transfer (ET) from pairs of ytterbium ions to europium ions. The ET rate was estimated by fitting a rate equation model with the dynamics of CUC red emission.

• OSTI ID: 21476511
• Journal Information: Journal of Applied Physics, Vol. 108, Issue 7; Other Information: DOI: 10.1063/1.3489992; (c) 2010 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DOPED MATERIALS
EMISSION SPECTRA
ENERGY TRANSFER
EUROPIUM IONS
EXCITATION
INFRARED SPECTRA
PHOTOLUMINESCENCE
POWDERS
RELAXATION
SYNTHESIS
ULTRAVIOLET RADIATION
ULTRAVIOLET SPECTRA
VISIBLE RADIATION
VISIBLE SPECTRA
X-RAY DIFFRACTION
YTTERBIUM IONS
YTTRIUM SILICATES
CHARGED PARTICLES
COHERENT SCATTERING
DIFFRACTION
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY-LEVEL TRANSITIONS
IONS
LUMINESCENCE
MATERIALS
OXYGEN COMPOUNDS
PHOTON EMISSION
RADIATIONS
SCATTERING
SILICATES
SILICON COMPOUNDS
SPECTRA
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS