title: The crystal structure, oxygen nonstoichiometry and chemical stability of Ba(0.5)Sr(0.5)Co(0.8)Fe(0.2)O(3-δ) (BSCF).
abstract: The oxygen nonstoichiometry and the crystal structure of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) were investigated by using coulometric titration, high-temperature gravimetry and in situ HT-XRD. The chemical stability diagram of BSCF was established as a function of temperature between room temperature and 1373 K and oxygen partial pressure, p(O2), between 1 and 1 × 10(-21) bar. The results showed that the cubic BSCF had poor chemical stability both under highly oxidative conditions at low temperatures and highly reductive conditions at high temperatures. The phase analysis of the decomposition products showed that the chemical instability of BSCF was mainly owing to the oxidation/reduction of trivalent Co ions.
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan. f-wang@mail.tagen.tohoku.ac.jp.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
authors.forename: Keiji
authors.initials: K
authors.lastname: Yashiro
authors.forename: Junichiro
authors.initials: J
authors.lastname: Mizusaki
authors.forename: Koji
authors.initials: K
authors.lastname: Amezawa