التفاصيل البيبلوغرافية
| العنوان: |
Structural, dielectric and Raman spectroscopy investigations of Ba1–xBi2x/3(Fe0.5Nb0.5)0.025Ti0.975O3 ceramics. |
| المؤلفون: |
Khedhri, Mohamed Hassen, Abdelmoula, Najmeddine, Khemakhem, Hamadi |
| المصدر: |
Applied Physics A: Materials Science & Processing; Mar2023, Vol. 129 Issue 3, p1-10, 10p, 1 Black and White Photograph, 3 Charts, 7 Graphs |
| مصطلحات موضوعية: |
RELAXOR ferroelectrics, RAMAN spectroscopy, DIELECTRICS, DIELECTRIC properties, SPECTRAL sensitivity, RAMAN scattering, LEAD titanate |
| مستخلص: |
This research work reports the structural, dielectric, and Raman scattering studies of Ba1–xBi2x/3(Fe0.5Nb0.5)0.025Ti0.975O3 (x = 0–0.15) polycrystalline samples synthesized by the solid state reaction method. The crystalline structure, Raman, and dielectric properties were investigated. The ceramic samples whose compositions x ≤ 0.075 exhibit a tetragonal P4mm symmetry, while the compositions with 0.10 ≤ x ≤ 0.15 crystallize in a cubic phase with a Pm 3 ¯ m space group. Dielectric studies reveal a transition from classical to relaxor ferroelectrics with an increasing substitution rate x in Ba1–xBi2x/3(Fe0.5Nb0.5)0.025Ti0.975O3 ceramics. The relaxor behavior observed for 0.10 ≤ x ≤ 0.15 was highlighted by a significant dielectric anomaly, in which the maximum temperature Tm was substantially dependent on frequency and went towards low temperature with rising Bi. For the compound x = 0.15, the maximum of ε r ′ is around 3000 at room temperature (293 K) and the value of ΔTm is 33 K. These values of ε r ′ and ΔTm are very important for relaxor materials by comparing them with those that are already published in the literature. The relaxor behavior was modeled using the Vogel–Fulcher relation. The Raman spectroscopy analysis demonstrates that the influence of the rate of Ba2+ substitution by Bi3+ may be shown via E (TO2) and A1 (TO3) modes. In the same line, the substantial displacement at the off-centered A location can be attributed to the Bi impurity causing the formation of polar clusters, which drove the transition from classical to relaxor ferroelectrics. This is supported by the stereochemical effect of the 6s2 lone pair electrons of Bi3+ as well as the significant ionic radius difference between Ba2+ and Bi3+. Furthermore, a thermal study of Raman spectral response to composition backs up our dielectric findings. [ABSTRACT FROM AUTHOR] |
|
Copyright of Applied Physics A: Materials Science & Processing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
| قاعدة البيانات: |
Complementary Index |
Find this article in full text from Springer Verlag. 
Full Text Finder