Surface degradation of strontium-based perovskite electrodes of solid oxide fuel cells

JOURNAL OF POWER SOURCES

卷:438

Article

Patel, Nripendra K.¹  Utter, Robert G.¹  Das, Diganta¹  Pecht, Michael¹ 

[1] Univ Maryland, Ctr Adv Life Cycle Engn, College Pk, MD 20742 USA

关键词: Solid oxide fuel cells;    Strontium-based perovskite electrodes;    Surface degradation;    Phase decomposition;    Degradation mechanisms;    Surface resistance;   

DOI  :  10.1016/j.jpowsour.2019.227040

来源: Elsevier

【 摘 要 】

Solid oxide fuel cells (SOFCs) are chemical-to-electrical energy conversion devices that consist of ceramic and metallic materials. The electrodes of SOFCs function as sites for electrochemical reactions, and as electronic conductors to transfer charge. The strontium-based perovskite electrode has been considered because it offers ionic and electronic conductivity, and tolerance to reduction-oxidation cycling. However, as shown in this work, exposure to humidity greater than 40% relative humidity, that may be present during non-operation conditions, including storage, can result in changes in the electrode surface composition with resulting degradation of electrical performance. This study investigates the physical-chemical and electrical characteristics of electrode surfaces when subjected to various humidity and temperature conditions, using scanning electron microscopy, energy dispersive spectroscopy, X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction techniques. Electrode phase decomposition, along with strontium-based degradation mechanisms, were found at humidity levels greater than 40% relative humidity.

【 授权许可】

Free