A Perovskite-Type Lanthanum Cobaltite Thin Film Synthesized via an Electrochemical Route and Its Application in SOFC Interconnects

Abstract

Metal oxides with a perovskite structure have attracted great interest in a wide range of technical applications, including solid oxide fuel cells (SOFCs), owing to their unique electronic, chemical, and structural features. Recently, significant efforts have been put into developing simple and cost-effective methodologies to controllably produce perovskite oxide layers for SOFC applications. In this study, we demonstrate the fabrication of a perovskite-type lanthanum cobaltite (LaCoO3) film via a facile electrochemical route and its feasibility as a conductive coating for metallic interconnects in SOFCs. A uniform, dense, and adhesive LaCoO3 film with a thickness of about 1 mu m (mixed with a small amount of Co3O4) is formed on a cobalt-coated stainless steel substrate through an electrodeposition process involving nitrate reduction and hydroxide precipitation, followed by thermal conversion in air. The fabricated perovskite film serves as an efficient conductive coating that can mitigate degradation in the electrical properties of metallic interconnects under typical SOFC operating conditions.