کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7888812 1509796 2018 37 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Multiplicity of photoluminescence in Raman spectroscopy and defect chemistry of (Ba1−xRx)(Ti1−xHox)O3 (R = La, Pr, Nd, Sm) dielectric ceramics
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Multiplicity of photoluminescence in Raman spectroscopy and defect chemistry of (Ba1−xRx)(Ti1−xHox)O3 (R = La, Pr, Nd, Sm) dielectric ceramics
چکیده انگلیسی
(Ba1−xRx)(Ti1−xHox)O3 (R = La, Pr, Nd, Sm; x ≥ 0.04) (BRTH) ceramics were prepared using a mixed oxides method. The solubility limits in BRTH with R = La, Pr, Nd, Sm were determined by XRD to be x = 0.11, 0.12, 0.06, and 0.14, respectively. The ionic radius of R at Ti-site plays a decisive role in the solubility limit in BRTH. Only BRTH with R = La satisfied Vegard's law. The multiplicity of photoluminescence (PL) signals of Nd3+/Ho3+ and Sm3+/Ho3+ in Raman scattering under 532-nm excitation laser and the high-permittivity abnormality for the denser BRTH with R = Sm and at x = 0.07 were reported. The PL provided the evidence of a small number of Ho3+ at Ba-site in BRTH and it was determined that the number of Ba-site Ho3+ ions increased from 0.05 at% at R = La to 0.19 at% at R = Sm with increasing atomic number of light rare earth. BRTH exhibited a much broadened dielectric-temperature characteristics, marked by ×5 T, ×6 T, ×7 T, and ×8 S dielectric specifications for BRTH with R = La, Pr, Nd, Sm and at x = 0.06, respectively, and they exhibited lower dielectric loss (tan δ < 0.015) at room temperature. The dielectric-peak temperature (Tm) of BRTH decreased linearly at a rate of less than −21 °C/%(R/Ho). The defect chemistry, solubility limit, lower dielectric loss, and dielectric abnormality are discussed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ceramics International - Volume 44, Issue 2, 1 February 2018, Pages 1483-1492
نویسندگان
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