A high-performance double perovskite air electrode material Sr2FeCo0.2Ni0.2Mo0.6O6-δ for reversible solid oxide cells

• Published in: Journal of power sources 2025-02, Vol.629, p.236063, Article 236063
• Main Authors: Li, Cheng, Tang, Yujie, Liu, Bo, Liu, Yaping, Zhu, Jianghuaxiong, Yan, Dong, Li, Jian, Jia, Lichao
• Format: Article
• Language: English
• Subjects: Air electrode; Double perovskite; Reversible solid oxide cells
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2024.236063

Reversible solid oxide cells (RSOCs) are highly efficient energy conversion devices, with air electrodes playing a crucial role in their performance. This study presents the preparation of a high-performance material, double perovskite Sr2FeCo0.2Ni0.2Mo0.6O6-δ (SFCNM), as an air electrode for RSOCs. The fundamental physicochemical properties of SFCNM suggest its suitability for this application. The synthesized SFCNM exhibits a double perovskite structure (I4/m) without any elemental segregation. Its average thermal expansion coefficient is measured at 17.7 × 10−6 K−1 from 200 to 800 °C, and it achieves a maximum electrical conductivity of 22.1 S cm−1 in air, meeting the essential requirements for an effective air electrode. Furthermore, the high concentration of oxygen vacancies on the surface of SFCNM enhances the kinetics of oxygen reduction and evolution reactions. The hydrogen electrode supported single cell with SFCNM-Gd0.1Ce0.9O2-δ (GDC) air electrode demonstrates outstanding performance in both solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC) modes. Additionally, short-term stability tests in both SOFC and SOEC modes, along with reversible cycle tests, further confirm that SFCNM is a promising air electrode material for intermediate-temperature RSOCs. •Sr2FeCo0.2Ni0.2Mo0.6O6-δ (SFCNM) was successfully prepared for RSOCs air electrode.•SFCNM has good electrical conductivity and abundant surface oxygen vacancies.•At 750 °C, 1.35 W cm−2 and -1.41 A cm−2 were achieved for SOFC and SOEC, respectively.