Superfast oxygen exchange kinetics on highly epitaxial LaBaCo2O5+δ thin films for intermediate temperature solid oxide fuel cells

Abstract

Superfast chemical dynamics on highly epitaxial LaBaCo2O5+δ (LBCO) heterostructures were systematically studied with symmetric half-cell LBCO/Gd0.2Ce0.8O2 (GCO):Y0.08Zr0.92O2 (YSZ)/LBCO heterostructures on (001) LaAlO3. The electrochemical impedance spectroscopy measurements reveal that the LBCO film electrodes have an ultralow polarization resistance as low as 0.11 Ω cm2 at 600 °C in air, a superfast surface exchange coefficient of 0.017 cm/s at 600°, and an extremely low activation energy value of 0.49 eV. These excellent physical chemistry properties and superfast chemical dynamics on the highly epitaxial LBCO thin films are considered to be somewhat related to the structure entropy of the nano ordered oxygen vacancy structure.