کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5440752 1398237 2017 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Electrical and transparent properties induced by structural modulation in (Sr0.925Ca0.075)2.5-0.5xNa xNb5O15 ceramics
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Electrical and transparent properties induced by structural modulation in (Sr0.925Ca0.075)2.5-0.5xNa xNb5O15 ceramics
چکیده انگلیسی
The effects of Na+ concentration on the microstructural, dielectric, ferroelectric and transparent properties of (Sr0.925Ca0.075)2.5-0.5xNa xNb5O15 (SCNN; 0.4 ≤ x ≤ 1.0) ceramics prepared using a conventional solid-state reaction method were investigated. X-ray diffraction results showed that the phase structure transitioned from tetragonal to orthorhombic tungsten bronze along with the structural type changing from 'unfilled' to 'filled' state. The NbO6 octahedron became more distorted and had higher interaction strength when introducing Na+ in A-sites to decrease the structural vacancies, leading to the improvement of dielectric and ferroelectric properties. The dielectric spectra of all specimens showed two broad dielectric anomalies: a high-temperature anomaly (the ferroelectric phase transition) and a low-temperature anomaly caused by the subtle structural effects in 'unfilled' SCNN ceramics, which evolved into the ferroelastic phase transition in 'filled' SCNN ceramics.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the European Ceramic Society - Volume 37, Issue 7, July 2017, Pages 2605-2613
نویسندگان
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