One-pot synthesis of mixed ionic-electronic conducting nanocomposites comprised of fluorite-like and perovskite-like phases as catalytic materials for SOFC

Nanocomposites comprised of fluorite-like (doped ceria) and perovskite- like (doped manganite) phases were prepared using a polymerized precursor (Pechini) route and two sources of lanthanides (Ln) - either pure Gd and Ce salts or an industrial ceria-rich mixture of Ln carbonates. Genesis of the structure of composites with annealing temperature has been studied by X-ray diffraction, Transmission Electron Microscopy and Raman. Up to 1300 o C, particle sizes of both fluorite and perovskite phases remain in the nano-range. Nanocomposites possess a high conductivity, lattice oxygen mobility and reactivity with respect to methane exceeding that of individual phases. They are also good catalysts for oxidation of decane by O2 without coking. Nanocomposite prepared from the industrial Ln source demonstrates better performance than that prepared from pure salts.