کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9761797 1498428 2005 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Oxygen vacancy formation and defect structure of Cu-doped lanthanum chromite LaCr0.79Cu0.05Al0.16O3−δ
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Oxygen vacancy formation and defect structure of Cu-doped lanthanum chromite LaCr0.79Cu0.05Al0.16O3−δ
چکیده انگلیسی
The results of oxygen nonstoichiometry are presented for the chromite LaCr0.79Cu0.05Al0.16O3−δ with hexagonal perovskite structure at 1000 °C. The modeling of the defect structure of this oxygen deficient chromite is carried out by considering also the acceptor dopant Cu on B-site. The equilibrium constants, necessary to calculate all a priori unknown equilibrium defect concentrations, are determined by fitting the derived model equation to the measured oxygen nonstoichiometry. The three oxidation states 3+, 2+, and 1+ for copper are considered simultaneously in Cu-doped lanthanum chromite in addition to 3+ and 4+ states for chromium in the host lattice. The results of the fitting revealed that there is no significant change of the Cr3+ oxidation state over the complete oxygen partial pressure range investigated (−20≤log(pO2/atm)≤0). In contrast to this, copper changes its oxidation state continuously from 3+ via 2+ to 1+ if the oxygen partial pressure decreases thereby giving rise to oxygen vacancy formation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Ionics - Volume 176, Issues 3–4, 31 January 2005, Pages 417-421
نویسندگان
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