کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1609242 1516255 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Small polaron conduction in lead modified lanthanum ferrite ceramics
ترجمه فارسی عنوان
هدایت پلارون کوچک در سرامیک فرایند لانتانیم اصلاح شده
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
چکیده انگلیسی
In the present work we have illustrated the physics of the electrical characteristics of nanocrystalline La1−xPbxFeO3, (0 ⩽ x ⩽ 0.2) powder prepared using auto-combustion synthesis. The effect of lead doping on the dielectric, impedance and ac conductivity characteristics of lanthanum ferrite has systematically been investigated. The synthesized powders were phase pure and crystallized into centro-symmetric Pnma space group. As compared to pure LaFeO3 ceramics (dielectric constant ∼ 14,000), the dielectric constant is grossly increased (∼30,000) in Pb doped LaFeO3. The temperature dependence of dielectric constant of 10.0 at.% Pb doped LaFeO3 exhibits dielectric maxima similar to that observed in ferroelectric ceramics with non-centrosymmetric point group. For La0.8Pb0.2FeO3 ceramics, the frequency dependence of the dielectric constant and loss tangent at various temperatures (300-450 K) exhibit typical colossal dielectric constant (CDC) like behavior. From the impedance spectroscopy we have estimated the grain and grain boundary resistance and capacitance of Pb doped LaFeO3 that follow a small polaron hopping conduction model. Long range movement of the charge carriers govern the CDC behavior.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volume 638, 25 July 2015, Pages 334-343
نویسندگان
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