کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10710252 1024661 2005 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Determination of oxygen stoichiometry in the mixed-valent manganites
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Determination of oxygen stoichiometry in the mixed-valent manganites
چکیده انگلیسی
The possible redox (oxidation reduction) chemical methods for precisely determining the oxygen content in the perovskite manganites including hole-doped La1−xCaxMnOy and electron-doped La1−xTexMnOy compounds are described. For manganites annealed at different temperatures, the oxygen content of the samples was determined by a redox back titration in which the powder samples taken in a quartz crucible were dissolved in (1+1) sulfuric acid containing an excess of sodium oxalate, and the excess sodium oxalate was titrated with permanganate standard solution. The results indicate that the method is effective and highly reproducible. Moreover, the variation of oxygen content is also reflected in significant change in the electrical transport property of the samples, which is mainly considered to be closely related to the introduction of oxygen vacancies in the Mn-O-Mn network.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetism and Magnetic Materials - Volume 285, Issue 3, January 2005, Pages 417-421
نویسندگان
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