Smart utilization of cobaltite-based double perovskite cathodes on barrier-layer-free zirconia electrolyte of solid oxide fuel cells

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2016-01, Vol.4 (48), p.1919-1925
• Main Authors: Li, Meng, Chen, Kongfa, Hua, Bin, Luo, Jing-li, Rickard, William D. A, Li, Jian, Irvine, John T. S, Jiang, San Ping
• Format: Article
• Language: English
• Subjects: Cathodes; Cerium oxide; Electrolytes; Energy density; Perovskites; Solid oxide fuel cells; Yttria stabilized zirconia; Zirconium dioxide
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c6ta08396j

Cobaltite-based double perovskite oxides with high electrocatalytic activity and conductivity have been developed as high-performance cathode alternatives for solid oxide fuel cells (SOFCs). However, the use of cobaltite-based double perovskites on Y 2 O 3 stabilized ZrO 2 (YSZ)-based SOFCs requires the application of a doped ceria barrier layer. This is due to their poor chemical and physical compatibility with the YSZ electrolyte during high-temperature sintering and fabrication processes. Here we report a viable approach to in operando assemble double perovskites such as PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+ δ (PBSCF), on YSZ electrolyte and thus effectively form an electrode/electrolyte interface without high-temperature processing. The electrochemical performance of the in situ assembled PBSCF cathode is comparable to that of the cathode prepared by conventional methods. A single cell with an in situ assembled PBSCF-GDC (Gd-doped ceria) cathode achieved a peak power density (PPD) of 1.37 W cm −2 at 750 °C and exhibited a high stability at 500 mA cm −2 and 750 °C for 100 h. Surface and cross-sectional microstructure analysis offer solid evidence that the PBSCF-GDC cathode/YSZ electrolyte interface was formed by electrochemical polarization. This work offers new opportunities to effectively and effortlessly use high-performance double perovskite cathodes in commercial SOFCs. Cathode/electrolyte interface could be formed by electrochemical polarization, offering new opportunities for direct application of double perovskites to YSZ-based SOFCs.