Реферат: PrNi1-xCoxO3-δ – Ce0.9Y0.1O2-δ composites are promising as IT SOFC cathodes provided their sintering conditions are optimized. In this work effect of microwave sintering (MS) on properties of such materials is studied. Perovskite (P) PrNi0.5Co0.5O3-δ (PNC) and fluorite (F) Ce0.9Y0.1O2 (YDC) oxides were synthesized by Pechini route. PNC ‒ YDC composites were prepared by ultrasonic dispersion of the oxides mixture in isopropanol. Pellets made from powders were sintered at 870 – 1100 °C using specially designed microwave set-up. Phase composition was determined by X-ray diffraction, microstructure and elemental composition – by TEM with EDX. Oxygen mobility and reactivity were estimated by O2 TPD (up to 800 oC) and oxygen isotope heteroexchange with 18O2 and C18O2 in static and flow reactors. MS provides dense materials (porosity < 10 %) even at the lowest temperatures. PNC is single-phase perovskite with minor admixtures of Pr6O11 or Pr4Co3O10. Composites are comprised of P+F phases with some Pr6O11 admixture, strong elements redistribution between P and F domains occurs. The total amount of oxygen desorbed is up to 20 monolayers for PNC (Tmax ~ 800 oС) and 70 monolayers for PNC – YDC (Tmax ~ 500 °C), being ~ 1.5 times higher as compared to conventionally sintered (CS) samples. This is due to a higher disordering of P and F domains as well as their boundaries for MS samples. The oxygen isotope exchange is characterized by R2 mechanism with the surface exchange constant kex ~ 10 6 cm/s at 700 °C for both PNC and PNC – YDC, being close to CS samples. The oxygen diffusion coefficient DO for highly mo-bile oxygen in nanocomposite is ~10 -8 cm2/s at 700 °C, which is also close to that for the best CS samples made at higher temperatures. Hence, MS at lower temperatures provides even better functional characteristics of PNC- YDC nanocomposite cath-odes.

Библиографическая ссылка: Sadykov V.A. , Eremeev N.F. , Bolotov V.A. , Tanashev Y.Y. , Fedorova Y.E. , Amanbaeva D.G. , Bobin A.S. , Sadovskaya E.M. , Muzykantov V.S. , Pelipenko V.V. , Lukashevich A.I. , Krieger T.A. , Ishchenko A.V. , Smirnova A.L.
Oxygen Mobility in Microwave Sintered Praseodymium Nickelates-Cobaltites and Their Nanocomposites with Yittria-Doped Ceria
20th International Conference on Solid State Ionics (SSI-20) 14-19 Jun 2015