Quantitative determination of site occupancy of multi-rare-earth elements doped into Ca{sub 2}SnO{sub 4} phosphor by electron channeling microanalysis

Journal Article · Wed Sep 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2010.07.026· OSTI ID:21432479

Fujimichi, Y ^[1]; Muto, S ^[1]; Tatsumi, K ^[1]; Kawano, T; Yamane, H ^[2]

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1. Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan)
2. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)

X-ray fluorescence analysis based on electron channeling effects in transmission electron microscopy (TEM) was performed on Ca{sub 2}SnO{sub 4} phosphor materials doped with Eu{sup 3+}/Y{sup 3+} at various concentrations, which showed red photoluminescence associated with the {sup 5}D{sub 0}-{sup 7}F{sub 2} electric dipole transition of Eu{sup 3+} ions. The method provided direct information on which host element site dopant elements occupy, the results of which were compared with those of X-ray diffraction (XRD)-Rietveld analysis. The obtained results indicated that while it is not favorable for a part of Eu{sup 3+} to occupy the smaller Sn{sup 4+} site, this is still energetically better than creating Ca vacancies or any other of the possible charge balance mechanisms. The local lattice distortions associated with dopant impurities with different ionic radii were also examined by TEM-electron energy-loss spectroscopy (TEM-EELS). The change in PL intensity as a function of dopant concentration is discussed based on the experimental results, although the general concept of concentration quenching applies. - Abstract: The composition of Ca{sub 1.8}Eu{sub 0.2}Y{sub 0.2}Sn{sub 0.8}O{sub 4} determined by electron channeling microanalysis is graphically shown, where the rare-earth dopants, Eu and Y preferentially occupy the Ca and Sn sites, respectively, to maintain the local charge neutrality.

• OSTI ID: 21432479
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 9; Other Information: DOI: 10.1016/j.jssc.2010.07.026; PII: S0022-4596(10)00308-7; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM COMPOUNDS
DOPED MATERIALS
E1-TRANSITIONS
ELECTRON CHANNELING
ENERGY-LOSS SPECTROSCOPY
EUROPIUM IONS
MICROANALYSIS
PHOTOLUMINESCENCE
QUENCHING
STANNATES
TIN IONS
TRANSMISSION ELECTRON MICROSCOPY
VACANCIES
X-RAY DIFFRACTION
X-RAY FLUORESCENCE ANALYSIS
YTTRIUM IONS
ALKALINE EARTH METAL COMPOUNDS
CHANNELING
CHARGED PARTICLES
CHEMICAL ANALYSIS
COHERENT SCATTERING
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
EMISSION
ENERGY-LEVEL TRANSITIONS
IONS
LUMINESCENCE
MATERIALS
MICROSCOPY
MULTIPOLE TRANSITIONS
NONDESTRUCTIVE ANALYSIS
OXYGEN COMPOUNDS
PHOTON EMISSION
POINT DEFECTS
SCATTERING
SPECTROSCOPY
TIN COMPOUNDS
X-RAY EMISSION ANALYSIS