Study on the Reaction and Degradation Mechanisms of Electrodes for Solid Oxide Electrochemical Cells Using a Model Electrode

Abstract

Solid oxide cells (SOCs) have emerged as promising energy conversion and storage devices owing to their high efficiency, fuel flexibility, and compatibility with renewable energy sources. Nevertheless, the widespread commercialization of SOCs faces critical challenges related to both performance degradation and long-term stability. In particular, issues such as high-temperature-induced phase instability and sluggish electrode reactions under reduced operating temperatures have become major obstacles. Accordingly, there is an urgent need for a deeper understanding of the mechanisms governing performance deterioration and material degradation to guide the development of durable and high-performance SOC systems. To address these challenges, this study employed dense bulk electrodes fabricated via ceramic processes to investigate electrode reaction mechanisms under realistic SOC operating environments. By eliminating structural ambiguities associated with porous electrodes, dense bulk electrodes provide a robust and reliable platform for the detailed analysis of surface exchange reactions and degradation phenomena. Utilizing this platform, the reaction behavior and stability of perovskite and double perovskite electrodes were systematically examined under both solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC) conditions, providing key insights into the intrinsic degradation mechanisms of electrode materials.