کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1296952 1498379 2008 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Transport properties of the double B mixed perovskite series La0.6Ca0.4Mn1 − xNixO3 − δ with x = 0-0.6
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Transport properties of the double B mixed perovskite series La0.6Ca0.4Mn1 − xNixO3 − δ with x = 0-0.6
چکیده انگلیسی
Double B perovskite-type series in the system La0.6Ca0.4Mn1 − xNixO3−δ with x = 0-0.6 was synthesized for the first time in air by solid state reactions at 1200 °C from simple oxides and CaCO3. Single phase compositions with small impurities of NiO-MnO solid solutions were formed. Replacement of Mn cations with Ni cations is accompanied by strong increase in electrical conductivity of the prepared ceramics. Lower conductivities of the Ni containing compositions compared to La0.6Ca0.4MnO3 − δ are explained by stronger polarization of the -Mn(α + γ)+-Oα−−Ni(α − γ)+-Oα−− fragments of the -Oα−-Mnα+-Oα−-Mnα+-Oα−-Mn(α + γ)+-Oα−-Ni(α − γ)+-Oα− chains in comparison with the -Oα−-Mnα+-Oα−-Mnα+-Oα− chains without Ni-cations, because of different electronegativity values of Ni and Mn. The compositions with x = 0-0.1 and x = 0.6 are p-type and those with x = 0.2-0.5 are n-type semiconductors. Type and level of the electrical conductivity of the La0.6Ca0.4Mn1 − xNixO3 − δ series are the functions of the [Mn4+]/[Mn3+] and [Ni3+]/[Ni2+] ratios. Mn4+ Ni4+ and Ni2+-cations are possible point defects which determine the p- and n-type conductivity of compositions, respectively.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Ionics - Volume 179, Issues 1–6, 31 March 2008, Pages 135-142
نویسندگان
, , , , , , ,