Enhancing surface activity of La0.6Sr0.4CoO3-δ cathode by a simple infiltration process

Abstract

Nanoscaled La0.6Sr0.4CoO3−δ (LSC) prepared by infiltration has been investigated as an effective catalyst to promote oxygen reduction reaction (ORR) performance for solid-oxide fuel cell. The area specific resistance of original cathode is appreciably reduced by the infiltration of LSC nanoparticles into the porous backbones of LSC cathode. The Arrhenius plots reveal that the reduction is originated from the pre-exponential factor, not the activation energy, suggesting that the rate of ORR has been enhanced by the infiltrated LSC nanoparticles. The infiltrated cell shows a high power density of 800 mW cm−2 at 700 °C, which is more than two times higher than those measured in the same conditions for a similar cell with pristine LSC cathode. Our results demonstrate that simple infiltration process without further heating at high temperature is a potential way to enhance electrochemical performance and to reduce the operating temperature.