Solid State Ionics, Vol.192, No.1, 269-274, 2011
High-temperature transport properties of La0.1Sr0.9Co0.8Fe0.2O3-delta
The transport properties of La0.1Sr0.9Co0.8Fe0.2O3-delta (LSCF1982) were measured by oxygen permeation measurements (850 <= T/degrees C <= 950, and 1 <= pO(2)/atm <= 10(-4)) and the chemical-diffusion coefficient was extracted from DC conductivity relaxation measurements. The maximum oxygen permeation flux was 1.17 cm(3)/min cm(2) 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 degrees C in nitrogen condition, which strongly supports the potential for catalytic application. The maximum total conductivity was around 1 x 10(3)S/cm at 500 degrees C in air, and the oxygen exponent m, applied in the equation sigma(tot) = P-O2(m), was assigned a value of 1/6 at the investigated temperature range. The chemical-diffusion coefficient ((D) over tilde) and surface exchange coefficient (k) were also calculated from the DC conductivity relaxation measurement and the values were best fitted by the following two equations: (D) over tilde (cm(2)/s) = 1.04 x 10 degrees exp(-0.58 +/- 0.01eV/KT), k(cm/s) = 1.09 x 10(1) exp (-0.77 +/- 0.06eV/KT) (C) 2010 Elsevier B.V. All rights reserved.