کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10629678 991139 2012 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High-temperature conductivity, stability and redox properties of Fe3−xAlxO4 spinel-type materials
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
High-temperature conductivity, stability and redox properties of Fe3−xAlxO4 spinel-type materials
چکیده انگلیسی
Iron-based oxides are considered as promising consumable anode materials for high temperature pyroelectrolysis. Phase relationships, redox stability and electrical conductivity of Fe3−xAlxO4 spinels were studied at 300-1773 K and p(O2) from 10−5 to 0.21 atm. Thermogravimetry/XRD analysis revealed metastability of the sintered ceramics at 300-1300 K. Low tolerance against oxidation leads to dimensional changes of ceramics upon thermal cycling. Activation energies of the total conductivity corresponded to the range of 16-26 kJ/mol at 1450-1773 K in Ar atmosphere. At 1573-1773 K and p(O2) ranging from 10−5 to 0.03 atm, the total conductivity of Fe3−xAlxO4 is nearly independent of the oxygen partial pressure. The conductivity values of Fe3−xAlxO4 (0.1 ≤ x ≤ 0.4) at 1773 K and p(O2) ∼10−5 to 10−4 atm were found to be only 1.1-1.5 times lower than for Fe3O4, showing high potential of moderate aluminium additions as a strategy for improvement of refractoriness for magnetite without significant deterioration of electronic transport.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the European Ceramic Society - Volume 32, Issue 12, September 2012, Pages 3255-3263
نویسندگان
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