Abstract
Oxygen-deficient BaSm(Cu0.5+xFe0.5-x)2O5+δ (x = -0.5, -0.45, -0.4, -0.1 and 0.0) double-perovskite samples have been successfully obtained by means of a novel synthesis technique utilizing an Fe/FeO getter encapsulated together with the starting material mixture in an evacuated silica-glass tube. The reducing conditions during the synthesis correspond to an oxygen partial pressure of approx. 7.6 × 10-16 atm. From X-ray diffraction (XRD), transmission electron micrographs (TEM) and energy-dispersive X-ray (EDX) analyses, the samples have been confirmed to be of essentially single phase. By post-annealing the as-synthesized samples under O2 or H2/Ar mixed gas, the amount of excess oxygen was controlled. Approaching δ ≈ 0 required prolonged annealing periods under reducing conditions. Samples having -0.4 < x < -0.1 did not form as a single-phase material under the present synthesis conditions.
Original language | English |
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Pages (from-to) | 121-125 |
Number of pages | 5 |
Journal | Physica C: Superconductivity and its Applications |
Volume | 338 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Aug 2000 |
MoE publication type | A4 Article in a conference publication |
Event | International Discussion Meeting on Chemistry Approaches to High-Tc Superconductive Materials / 5th International Workshop on Chemical Designing and Processing of High-Tc Superconductors (Chem-HTSC-V) - Yokohama, Jpn Duration: 15 Oct 1999 → 16 Oct 1999 |