Oxygen Nonstoichiometry and Ion-Electron Transport in SrFe0.9M0.1O3-δ (M=Cr, Ti, Al)
The total conductivity and oxygen deficiency of partially substituted strontium ferrite, SrFe0.9M0.1O3-δ (M=Cr, Ti, Al), at 700-950°C were measured depending on oxygen partial pressure varying in ranges 10-19-0.5 and 10-5-0.5 atm. The partial contributions of n- and p-type electronic charge carriers and oxygen ions to the electrical transport were determined analyzing the total conductivity vs. oxygen pressure dependencies. Additions of all dopants studied in this work are found to extend the cubic perovskite phase stability range and to improve oxygen transport in the intermediate-temperature range. The behavior of hole mobility suggests a polaron conduction mechanism. Doping with aluminum has a weak influence on the mobility level, while the incorporation of Cr and Ti cations into the ferrite lattice decreases hole mobility up to four times.
Paula Maria Vilarinho
M. V. Patrakeev, I.A. Leonidov, V.L. Kozhevnikov, V. V. Kharton, "Oxygen Nonstoichiometry and Ion-Electron Transport in SrFe0.9M0.1O3-δ (M=Cr, Ti, Al)", Materials Science Forum, Vols. 514-516, pp. 382-386, 2006