Conductivity and thermal expansion of the Ce0.8Gd0.2O1.9 solid electrolyte in the oxidizing and reducing atmospheres

摘要: Highly compact (99%) solid electrolyte Ce0.8Gd0.2O1.9 with submicron (0.3 μm) grains is synthesized. The dilatometric (20–850°C) and conductivity (180–350°C) measurements are performed on the in air as a function of partial oxygen pressure \(p_{O_2 } \) (0.21−1×10−25 atm) at 600, 700, 800°C. An inflection found temperature dependences thermal coefficient linear expansion (impedance measurements) ∼230°C, which evidence for phase transition. activation energies conduction grain bulk boundaries differ only slightly, indicating that boundaries’ resistance caused not by precipitation second boundaries, but most probably presence intergranular nanopores. confirm significant increase dimensions reducing atmospheres parallel its electron conductivity. specific elongation proportionally to }^{ - 1/4} all temperatures. values, transport numbers ions ti = 0.5, determined. They 10−22.5, 10−20, 10−18 atm 800°C, respectively.