La0.6Sr0.4CoO3 (LSC40) has been studied as an SOFC cathode. It is reported that the oxygen reduction reaction was enhanced at hetero-interface of LSC40 and La1.5Sr0.5CoO 4 (LSC155). Relationship between the electrode performance and the surface chemistry was elucidated to find out the mechanism of the heterointerface effect. Thin film electrodes of LSC40, LSC155, and double-layer electrode of LSC155-on-LSC40 were fabricated by pulsed laser deposition. The electrode performance was measured by impedance measurement. LSC40 electrode degraded during the measurement, and enrichment of strontium was observed at the surface of the degraded LSC40 by EDX analysis. On the other hand, the segregation of strontium was suppressed on the doublelayer electrode, whose electrode performance was relatively higher than that of LSC40 single-phase electrode. It implies that the layered LSC155 may suppress the electrode degradation.
ASJC Scopus subject areas