Preparation of SrFe0.6Cu0.3Ti0.1O3-δ Mixed Oxygen-Ionic and Electronic Conductor
SrFe0.6Cu0.3Ti0.1O3-δ (SFCTO) composite-oxide powder was synthesized by citric acid complex method and studied as mixed oxygen-ionic and electronic conducting membrane material. The formation process of the perovskite-type compound was detected by XRD, infra-red spectrum and thermo gravimetric analysis; the effects of ethylene glycol added in the sol formation process on the size distribution of the powder and the oxygen permeation flux of the membrane were examined. A stable sol was formed when the molar ratio of total metal ions to citric acid and ethylene glycol was 1:2:3 and the pH value was 5.5; the characteristic absorption peaks of citric acid in the dried gel, O-H and -COO-, moved toward low frequency direction for 200 cm-1 and 135 cm-1 respectively due to the complexing action of the metal ions and citric acid. As the dried gel was heated in air up to 400°C, SrCO3 phase appeared by the combustion of citric acid and ethylene glycol. The perovskite phase started to form at 700 °C, SrCO3 phase reduced gradually and the single phase of SFCTO was obtained at 900 °C. The SFCTO dense membrane prepared under the optimum conditions exhibited an oxygen permeation flux of 0.7 ml·min-1·cm-2 at 900°C.
Wei Pan and Jianghong Gong
H. Zhang et al., "Preparation of SrFe0.6Cu0.3Ti0.1O3-δ Mixed Oxygen-Ionic and Electronic Conductor", Key Engineering Materials, Vols. 368-372, pp. 259-262, 2008