Symmetrical solid oxide fuel cells (SSOFCs) show many advantageous features of simplifying fabrication process, minimizing interdiffusion between components and enhancing coking and sulfur tolerance by operating the anode as the cathode. In this paper, the double-perovskite Sr₂TiFe_0.9Mo_0.1O_6–δ (STFM01) and Sr₂TiFe_0.8Mo_0.2O_6–δ (STFM02) oxides are synthesized by the traditional solid-state reaction and assessed as symmetrical electrodes. Both of the two materials show cubic double perovskite structure with outstanding structural stability, well chemical compatibility and matched thermal expansion coefficients with the common electrolytes in oxidizing and reducing atmospheres under SOFC operating temperatures. From the electrochemical performance, the electrolyte-supported single cell with STFM01 electrode presents the maximum power densities of 573 mW cm⁻² in H₂ and 361 mW cm⁻² in complex hydrocarbon fuels containing H₂S at 850 °C, respectively. The electrochemical stability test exhibits that the STFM01 sample showed no any degradation in H₂ and acceptable degradation in hydrocarbon fuels, and STFM02 sample showed no any deterioration during 30-h test in hydrocarbon fuels, which implies that the STFM01 and STFM02 materials had remarkable ability of resisting carbon deposition and sulfur poisoning than the traditional anode material. The efficient and relatively stable double perovskite symmetrical electrodes are much more promising candidate materials for SSOFCs and are beneficial for realizing commercialization of SOFC.

对称固体氧化物燃料电池（SSOFC）具有许多有利的特征，可简化制造过程，使组件之间的相互扩散最小化并通过将阳极作为阴极运行来提高焦化和耐硫性。在本文中，双钙钛矿Sr ₂ TiFe _0.9 Mo _0.1 O _{6– δ}（STFM01）和Sr ₂ TiFe _0.8 Mo _0.2 O _{6– δ}（STFM02）氧化物是通过传统的固态反应合成的，并被评估为对称电极。两种材料均显示立方双钙钛矿结构，具有出色的结构稳定性，良好的化学相容性，并且在SOFC工作温度下的氧化和还原气氛中，热膨胀系数与普通电解质相匹配。从电化学性能来看，带有STFM01电极的电解质支持的单电池在850°C下的H ₂和含H ₂ S的复杂烃类燃料中的最大功率密度分别为573 mW cm ^-2和361 mW cm ^-2。电化学稳定性测试表明，STFM01样品在H _2中没有任何降解在碳氢燃料中经过30小时的测试后，STFM02样品没有出现任何劣化，这表明STFM01和STFM02材料比传统的阳极材料具有显着的抗碳沉积和硫中毒能力。高效且相对稳定的双钙钛矿对称电极是用于SSOFC的更有希望的候选材料，并且有利于实现SOFC的商业化。