Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics

Mustafa İlhan; Lütfiye Feray Güleryüz; Mehmet İsmail Katı

doi:10.18596/jotcsa.1790637

Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics

Abstract

The structural, microstructural, and dielectric properties of Eu3+-doped and Eu3+, B3+ co-doped Sr2GdTaO6 double perovskite ceramics were systematically investigated. X-ray diffraction (XRD) analysis confirmed that all samples crystallize in the monoclinic P2₁/n space group with long-range B/B′ ordering, remaining single-phase up to 20 mol% Eu3+ and 70 mol% B3+. The peak-shift analysis revealed a slight shift toward lower angles, attributed to the substitution of Gd3+ by Eu3+ and the indirect structural perturbations induced by boron incorporation through charge compensation and microstrain effects. Crystallite sizes, derived from Scherrer and Williamson–Hall analyses, were found in the 30–45 nm range, with microstrain and defect densities increasing under Eu3+ doping but significantly reduced at moderate B3+ contents, consistent with the fluxing effect of boron. Scanning electron microscopy (SEM) revealed dense, terraced grains of 4–13 µm in the Eu3+ series, while boron addition promoted grain growth up to ~25 µm and faceted morphologies at intermediate concentrations. Excessive boron, however, yielded heterogeneous microstructures and secondary phases, aligning with XRD observations. Dielectric measurements demonstrated frequency-dependent behavior consistent with the Maxwell–Wagner model. For the Eu3+ series, the dielectric constant decreased from 32.4 to 21.8 at 20 Hz with increasing Eu3+, reflecting reduced crystallinity and enhanced microstrain. In contrast, moderate boron addition significantly enhanced the dielectric constant (up to 45.7 at 20 Hz) and suppressed dielectric loss, owing to improved densification, larger grains, and reduced oxygen-vacancy-related conduction. At high boron contents (70 and 100 mol%), both ε′ and tan δ degraded, attributed to strain accumulation and secondary phase formation. These results establish clear correlations between defect chemistry, microstructure, and dielectric response in Sr2GdTaO6 ceramics, highlighting the potential of controlled Eu3+ substitution and optimized boron co-doping for tailoring multifunctional dielectric materials.

Keywords

References

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Details

Primary Language

English

Subjects

Crystallography, Optical Properties of Materials

Journal Section

Research Article

Authors

Mustafa İlhan ^*
0000-0001-7826-9614
Türkiye

Lütfiye Feray Güleryüz
0000-0003-0052-6187
Türkiye

Mehmet İsmail Katı
0000-0002-9225-730X
Türkiye

Publication Date

March 2, 2026

Submission Date

September 24, 2025

Acceptance Date

January 21, 2026

Published in Issue

Year 2026 Number: 2026-1

DOI

https://doi.org/10.18596/jotcsa.1790637

IZ

https://izlik.org/JA78DY64ZE

Cite

RIS / Bibtex

APA

İlhan, M., Güleryüz, L. F., & Katı, M. İ. (2026). Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics. Journal of the Turkish Chemical Society Section A: Chemistry, 2026-1, 1-15. https://doi.org/10.18596/jotcsa.1790637

AMA

1.İlhan M, Güleryüz LF, Katı Mİ. Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics. JOTCSA. 2026;(2026-1):1-15. doi:10.18596/jotcsa.1790637

Chicago

İlhan, Mustafa, Lütfiye Feray Güleryüz, and Mehmet İsmail Katı. 2026. “Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics”. Journal of the Turkish Chemical Society Section A: Chemistry, no. 2026-1: 1-15. https://doi.org/10.18596/jotcsa.1790637.

EndNote

İlhan M, Güleryüz LF, Katı Mİ (March 1, 2026) Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics. Journal of the Turkish Chemical Society Section A: Chemistry 2026-1 1–15.

IEEE

[1]M. İlhan, L. F. Güleryüz, and M. İ. Katı, “Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics”, JOTCSA, no. 2026-1, pp. 1–15, Mar. 2026, doi: 10.18596/jotcsa.1790637.

ISNAD

İlhan, Mustafa - Güleryüz, Lütfiye Feray - Katı, Mehmet İsmail. “Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics”. Journal of the Turkish Chemical Society Section A: Chemistry. 2026-1 (March 1, 2026): 1-15. https://doi.org/10.18596/jotcsa.1790637.

JAMA

1.İlhan M, Güleryüz LF, Katı Mİ. Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics. JOTCSA. 2026;:1–15.

MLA

İlhan, Mustafa, et al. “Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics”. Journal of the Turkish Chemical Society Section A: Chemistry, no. 2026-1, Mar. 2026, pp. 1-15, doi:10.18596/jotcsa.1790637.

Vancouver

1.Mustafa İlhan, Lütfiye Feray Güleryüz, Mehmet İsmail Katı. Structural, Microstructural, and Dielectric Insights into Eu3+-Doped and Eu3+, B3+ Co-Doped Sr2GdTaO6 Double Perovskite Ceramics. JOTCSA. 2026 Mar. 1;(2026-1):1-15. doi:10.18596/jotcsa.1790637