Electrode and oxygen permeation properties of (Ce, Sm)O2–MFe2O4 composite thin films (M = Co and Mn)

This paper describes the electrode and oxygen permeation properties of Sm-doped CeO2–MFe2O4 composites prepared on a Sm-doped CeO2 electrolyte, where M = Co and Mn. The porous and thin-film samples were prepared by means of citrate-based liquid-mix and chemical solution deposition techniques, respectively. For Cole–Cole plots of porous and thin-film electrodes, two semi-circles corresponding to interface and chemical impedances were observed. The thin-film electrode of 1-μm-thick (Ce0.9Sm0.1)O2–30 vol.%CoFe2O4 (30CFO) composites showed a current density of 509 mA/cm2 at 900 °C under a cathodic overpotential of 159 mV. The 30CFO thin film exhibited an oxygen flux density of 1.3 μmol/cm2 s at 900 °C under pO2 of 1.2 × 10− 20 atm.