High-temperature transport properties of La0.1Sr0.9Co0.8Fe0.2O3 − δ

The transport properties of La0.1Sr0.9Co0.8Fe0.2O3 − δ (LSCF1982) were measured by oxygen permeation measurements (850 ≤ T/°C ≤ 950, and1 ≤ pO2/atm ≤ 10− 4) and the chemical-diffusion coefficient was extracted from DC conductivity relaxation measurements. The maximum oxygen permeation flux was 1.17 cm3/min cm2 at air/He condition for the 1.5 mm-thick LSCF1982 specimen and the maximum oxygen ion conductivity was around 1 S/cm at 950 °C in nitrogen condition, which strongly supports the potential for catalytic application. The maximum total conductivity was around 1 × 103 S/cm at 500 °C in air, and the oxygen exponent m, applied in the equation σ tot = P O 2 m , was assigned a value of 1/6 at the investigated temperature range. The chemical-diffusion coefficient (D̃) and surface exchange coefficient (κ) were also calculated from the DC conductivity relaxation measurement and the values were best fitted by the following two equations: D ˜ ( cm 2 /s ) = 1.04 × 10 ° exp − 0.58 ± 0.01 eV K T ,   k ( cm/s ) = 1.09 × 10 1 exp − 0.77 ± 0.06 eV K T .