Nickel oxide-gadolinia-doped ceria thin films with a ceria composition of 80 at% Ce and 20 at% Gd were grown by pulsed laser deposition on sapphire and SiO2/Si wafers as well as on yttria stabilized zirconia polycrystalline substrates. Upon reduction of the NiO phase in a H2/N2 atmosphere at 600 degrees C, a stable three-phase, 3-D interconnecting microstructure was obtained of metallic Ni, ceramic, and pores. Coarsening and segregation of the Ni to the surface of the film was observed at higher temperatures.
View Article and Find Full Text PDFFour compositions of Ba(1-x)Sr(x)Co(1-y)Fe(y)O(3-delta) were studied for phase, oxygen uptake-release, and transition metal (TM) oxidation states after solid state processing and with in situ heating from 300 to 1273 K in air. X-Ray diffraction showed that all compositions except one had the cubic perovskite structure at all temperatures; that with x, y = 0.2 was a mixture as prepared, becoming predominantly cubic at high temperature.
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