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The volt-ampere and impedance characteristics of solid oxide fuel cells (SOFC) at 800°C depending on the structure of the anode, electrolyte, and cathode were studied. The combination of the 10Sc1CeSZ–NiO anode with the 10Sc1CeSZ electrolyte, the GDC barrier cathode layer, and the LSCF–GDC cathode leads to an increase in the electrical properties of this SOFC in 1.4 and 2.8 times compared to the SOFC of the 3.5YSZ–NiO/8YSZ/LSM–8YSZ system to the SOFC of the 10Sc1CeSZ–NiO/8YSZ/LSM–8YSZ system, respectively. At the same time, the incompatibility of the 10Sc1CeSZ–NiO anode and the 8YSZ electrolyte was revealed, which is associated with cerium migration during sintering of the half-cell. [ABSTRACT FROM AUTHOR]

Modified nickel composites based on stabilized zirconia as prototypes of anode materials of solid oxide fuel cells (SOFC) showed high catalytic activity and stability in the oxidative reforming of alkanes (tri-reforming of methane and steam-(oxygen) reforming of butane). Modification of Ni-10Sc1CeSZ composite with Cu and CeO2 increases its resistance to carbonization, and doping with platinum or palladium (0.1 wt.%) increases the resistance to H2S poisoning. Structured Ni-(CeO2, La2O3)-Al2O3/cordierite catalysts are characterized by high activity and stability in the oxidative reforming of C1-C3 alkanes into syngas and can be effective in an external processor integrated with SOFC. Bench tests of the fuel cell showed the achievement of acceptable electrical characteristics. [ABSTRACT FROM AUTHOR]

Total ionic, grain and grain boundary conductivity of traditional 8YSZ and promising 10Sc1CeSZ electrolytes for solid oxide fuel cells (SOFC) were studied. Samples were sintered at 1400°C due to best values of the ionic conductivity, as it was shown earlier. The total conductivity of 10Sc1CeSZ electrolytes at 600°C varied from 0.019 to 0.046 S/cm depending on the initial powder, and for 8YSZ it was 0.059 S/cm. The activation energies were 0.88–1.07 eV and 1.04 eV, respectively. The grain boundary conductivity prevails in YSZ electrolytes due to higher association enthalpy of the grain at temperatures below 560°C which depends on the dopant size. In 10Sc1CeSZ electrolytes the charge transfer passes mainly through the grains: the main contribution to the grain boundary resistivity is given by SiO2 segregations at the grain boundaries in technically pure materials; and grain-to-grain contacts in highly pure materials. The grain boundary resistivity drops twice due to presence of Al2O3 admixtures known for their scavenging effect on SiO2 segregations. [ABSTRACT FROM AUTHOR]

Nickel-containing composites based on stabilized zirconia (20Ni(Cu)/10Sc1CeSZ) modified by added ceriumdioxide (10 wt.%) (Ni-Cu-CeO2), and 0.1 wt.% platinum (Pt-Ni), or 0.1 wt.% palladium (Pd-Ni) showed high activity and stability in the tri-reforming of methane at 700-800 °C. The Pt-Ni and Pd-Ni catalysts are more resistant to the deactivating effect of admixture of H2S than the Ni-Cu-CeO2 composite. A longer regeneration time for the Pd-Ni catalyst helps restore its initial activity. [ABSTRACT FROM AUTHOR]

The change in porosity of the Ni-3.5YSZ (ZrO stabilized with 3.5 mol.% YO) composite, when produced, and the effect of porosity on the strength and electrical conductivity is studied. The porosity was provided by adding granular starch to the mixture of NiO and 3.5YSZ powders. The content of 18 vol.% pore-forming agent in the Ni-3.5YSZ cermet provides open porosity 47.1%, while its strength and electrical conductivity are 74.3 MPa and 0.93 · 10 S/m, respectively. [ABSTRACT FROM AUTHOR]

The structure of Ceria doped Scandia Stabilized Zirconia (1Ce10ScSZ) electrolyte film deposited by EB-PVD (Electron Beam-Physical Vapour Deposition) technique on NiO-ZrO substrate was characterized by electron microscopy. The highly porous substrate was densely covered by deposited film without any spallation. The produced electrolyte layer was of a columnar structure with bushes, bundles of a diameter up to 30 μm and diverse height. Between the columns, delamination cracks of few microns length were visible. The annealing of zirconia film at 1000 °C resulted in its densification. The columnar grains and delaminating cracks changed their shape into a bit rounded. High magnification studies revealed nanopores 5-60 nm formed along the boundaries of the columnar grains during annealing. High-quality contacts between the electrolyte film and anode substrate ensured good conductivity of the electrolyte film and high efficiency of SOFC. [ABSTRACT FROM AUTHOR]