(Bi,Sr) (Fe,M)O (M = Co, Ni and Mn) Cathode Materials with Mixed Electro-Ionic Conductivity.

(Bi,Sr)FeO (BSF) cathode materials doped with either Co, Ni or Mn are synthesized by an ethylene diamine tetra-acetic acid (EDTA)-citrate complexing method, and the effects of the doping level on the mixed electronic-ionic conductivity at various temperatures are studied up to 800 °C. The phase purity and solid solution limit are investigated by X-ray diffraction (XRD). The ionic conductivity is measured by the four-probe direct current (DC) method, the valence state of Fe and Mn by X-ray photoelectron spectroscopy (XPS), and the oxygen non-stoichiometry by differential thermo-gravimetric analysis (TGA).

Synthesis and Study on Ionic Conductive (Bi,V)O Materials with a Dual-Phase Microstructure.

Homogeneous Bi₂O₃-V₂O₅ powder mixtures with different amounts of V₂O₅ content (≤15 mol%) were prepared by colloidal dispersion and sintering to high density. The sintered and annealed samples were studied by thermal analysis, quantitative X-ray diffraction and scanning electron microscopy. The electrical and ionic conductivities of the conductors were also measured by a four-probe direct current (DC) method.