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Scandia-stabilized-zirconia is a potential zirconia-based electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). In this study, the properties of zirconia co-doped with 10 mol% Sc and 1 mol% Ce (scandia-ceria-stabilized-zirconia, 10Sc1CeSZ) electrolyte synthesized by the microwave-assisted glycine nitrate process (MW-GNP) were determined. The effects of microwave heating on the sintering temperature, microstructure, densification and ionic conductivity of the 10Sc1CeSZ electrolyte were evaluated. The phase identification, microstructure and specific surface area of the prepared powder were investigated using X-ray diffraction, transmission electron microscopy and the Brunauer-Emmett-Teller technique, respectively. Using microwave heating, a single cubic-phase powder was produced with nanosized crystallites (19.2 nm) and a high specific surface area (16 m2/g). It was found that the relative density, porosity and total ionic conductivity of the 10Sc1CeSZ electrolyte are remarkably influenced by the powder processing method and the sintering temperature. The pellet sintered at 1400 °C exhibited a maximum ionic conductivity of 0.184 S/cm at 800 °C. This is the highest conductivity value of a scandia-stabilized-zirconia based electrolyte reported in the literature for this electrolyte type. The corresponding value of the activation energy of electrical conductivity was found to be 0.94 eV in the temperature range of 500–800 °C. Overall, the use of microwave heating has successfully improved the properties of the 10Sc1CeSZ electrolyte for application in an IT-SOFC

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Nickel-based cermet anode can be operated in hydrogen and hydrocarbon-fuelled intermediate temperature solid oxide fuel cells (SOFCs). Nickel/zirconia co-doped with 10 mol% scandia and 1 mol% ceria (Ni/10Sc1CeSZ) has better electrochemical performance compared with the state-of-the art SOFC anode, Ni/yttria-stabilised-zirconia. In this study, nickel-metal/10 mol% scandia-1 mol% ceria-stabilised zirconia (Ni0.5M0.5/10Sc1CeSZ, M = Co, Cu and Fe) composite anode powders were synthesised via a single-step microwave-assisted glycine nitrate process. The phase identification and morphology of the prepared powder were investigated by X-ray diffraction and field-emission scanning electron microscopy, respectively. The carbon deposition properties of Ni/10Sc1CeSZ and Ni0.5M0.5/10Sc1CeSZ (M = Co, Cu and Fe) cermet anode in dry methane fuel were evaluated. Cermet anode powder was reduced under a mixture of hydrogen (10%) and nitrogen (90%) at 800 °C for 2 h prior to the carbon deposition test. In the carbon deposition test, the reduced cermet powder was exposed in dry methane atmosphere at 800 °C for 3 h. Overall, Ni0.5Cu0.5/10Sc1CeSZ cermet anode exhibits the highest intensity ratio of G/D (2.64) in Raman analysis, resulting in less amorphous carbon deposits. This study shows that copper metal substitution could suppress carbon deposition onto Ni/10Sc1CeSZ cermet, and this material can be used as an anode material for SOFCs that operate on dry methane fuel.