| Title of Article |
Fe3+/Nb5+ Co-doped rutile–TiO2 nanocrystalline powders prepared by a combustion process: preparation and characterization and their giant dielectric response |
| Date of Acceptance |
1 April 2020 |
| Journal |
| Title of Journal |
Royal Society of Chemistry Advances |
| Standard |
|
| Institute of Journal |
The Royal Society of Chemistry |
| ISBN/ISSN |
|
| Volume |
2020 |
| Issue |
10 |
| Month |
June |
| Year of Publication |
2020 |
| Page |
24784–24794 |
| Abstract |
Fe3+/Nb5+ co-doped TiO2 (FeNb-TO) nanocrystalline powders were prepared by a combustion process. A
pure rutile–TiO2 phase of powders and sintered ceramics with a dense microstructure was achieved. Both
co-dopants were homogeneously dispersed in the ceramic microstructure. The presence of oxygen
vacancies was confirmed by Raman and X-ray photoelectron spectroscopy techniques. The lowfrequency dielectric permittivity enhanced as co-doping concentration increased. The thermally
activated giant-dielectric relaxation of FeNb-TO ceramics was observed. Removing the outer-surface
layer had a slight effect on the dielectric properties of FeNb-TO ceramics. Density functional theory
(DFT) calculation showed that, in the energy preferable configuration, the 2Fe atoms are located near
the oxygen vacancy, forming a triangle-shaped FeVoTi defect complex. This defect cluster was far away
from the diamond-shaped 2Nb2Ti defect complex. Thus, the electron-pinned defect-dipoles (EPDD)
cannot be formed. The giant-dielectric relaxation process of the FeNb-TO ceramics might be attributed
to the interfacial polarization associated with electron hopping between Ti3+/Ti4+ ions inside the grains,
rather than due to the surface barrier layer capacitor (SBLC) or EPDD effect. |
| Keyword |
Rutile−TiO2, Giant dielectric permittivity, Combustion process |
| Author |
|
| Reviewing Status |
มีผู้ประเมินอิสระ |
| Status |
ตีพิมพ์แล้ว |
| Level of Publication |
นานาชาติ |
| citation |
true |
| Part of thesis |
true |
| ใช้สำหรับสำเร็จการศึกษา |
ไม่เป็น |
| Attach file |
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| Citation |
0
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Publication
Journal Publication
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