Abstract
A protocol for characterizing relaxation of anisotropic strain in thin films of 10 mol% Eu- or Sm-doped ceria is described. The method is based on comparison of Raman spectra and X-ray diffraction patterns from substrate-supported films, displaying in-plane compressive strain (initial state), with analogous data from 2 mm diameter self-supported films (i.e., membranes), prepared by partial substrate removal (final state). These membranes are found to be relaxed, i.e., approximately unstrained, but with increased unit cell volume. The effective (i.e., 2-state) Grüneisen parameter of the F2g Raman active mode for these films is calculated to be 0.4 ± 0.1, which is ≈30% of the literature value for the corresponding ceramics under isostatic pressure. On this basis, it is found that the observed red-shift of the F2g mode frequency following isothermal strain relaxation of the doped ceria thin films cannot be determined solely by the increase in average unit cell volume. The study presented here may shed light on the suitability of Raman spectroscopy as a technique for characterizing strain in lanthanide-doped ceria thin films.
| Original language | English |
|---|---|
| Article number | 1804433 |
| Journal | Advanced Functional Materials |
| DOIs | |
| Publication status | Accepted/In press - Jan 1 2019 |
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Keywords
- anelastic relaxation
- doped ceria
- Grüneisen parameter
- Raman spectroscopy
ASJC Scopus subject areas
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics
Cite this
Suitability of Raman Spectroscopy for Assessing Anisotropic Strain in Thin Films of Doped Ceria. / Kraynis, Olga; Makagon, Evgeniy; Mishuk, Eran; Hartstein, Michal; Wachtel, Ellen; Lubomirsky, Igor; Livneh, Tsachi.
In: Advanced Functional Materials, 01.01.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Suitability of Raman Spectroscopy for Assessing Anisotropic Strain in Thin Films of Doped Ceria
AU - Kraynis, Olga
AU - Makagon, Evgeniy
AU - Mishuk, Eran
AU - Hartstein, Michal
AU - Wachtel, Ellen
AU - Lubomirsky, Igor
AU - Livneh, Tsachi
PY - 2019/1/1
Y1 - 2019/1/1
N2 - A protocol for characterizing relaxation of anisotropic strain in thin films of 10 mol% Eu- or Sm-doped ceria is described. The method is based on comparison of Raman spectra and X-ray diffraction patterns from substrate-supported films, displaying in-plane compressive strain (initial state), with analogous data from 2 mm diameter self-supported films (i.e., membranes), prepared by partial substrate removal (final state). These membranes are found to be relaxed, i.e., approximately unstrained, but with increased unit cell volume. The effective (i.e., 2-state) Grüneisen parameter of the F2g Raman active mode for these films is calculated to be 0.4 ± 0.1, which is ≈30% of the literature value for the corresponding ceramics under isostatic pressure. On this basis, it is found that the observed red-shift of the F2g mode frequency following isothermal strain relaxation of the doped ceria thin films cannot be determined solely by the increase in average unit cell volume. The study presented here may shed light on the suitability of Raman spectroscopy as a technique for characterizing strain in lanthanide-doped ceria thin films.
AB - A protocol for characterizing relaxation of anisotropic strain in thin films of 10 mol% Eu- or Sm-doped ceria is described. The method is based on comparison of Raman spectra and X-ray diffraction patterns from substrate-supported films, displaying in-plane compressive strain (initial state), with analogous data from 2 mm diameter self-supported films (i.e., membranes), prepared by partial substrate removal (final state). These membranes are found to be relaxed, i.e., approximately unstrained, but with increased unit cell volume. The effective (i.e., 2-state) Grüneisen parameter of the F2g Raman active mode for these films is calculated to be 0.4 ± 0.1, which is ≈30% of the literature value for the corresponding ceramics under isostatic pressure. On this basis, it is found that the observed red-shift of the F2g mode frequency following isothermal strain relaxation of the doped ceria thin films cannot be determined solely by the increase in average unit cell volume. The study presented here may shed light on the suitability of Raman spectroscopy as a technique for characterizing strain in lanthanide-doped ceria thin films.
KW - anelastic relaxation
KW - doped ceria
KW - Grüneisen parameter
KW - Raman spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=85059520878&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85059520878&partnerID=8YFLogxK
U2 - 10.1002/adfm.201804433
DO - 10.1002/adfm.201804433
M3 - Article
AN - SCOPUS:85059520878
JO - Advanced Functional Materials
JF - Advanced Functional Materials
SN - 1616-301X
M1 - 1804433
ER -