减少热膨胀和提高电化学性能在Pr替代的SrFeO3作为固体氧化物燃料电池的对称电极
Abraham Sánchez-Caballero1,2, Javier Zamudio-García3, Lucía Dos Santos-Gómez1,2
1Dpto. de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, Malaga 29071, Spain.
ACS applied materials & interfaces
|March 27, 2025
概括
在铁氧化 (SrFeO3) 中的氧化兴奋剂可提高固氧化物燃料电池的电极性能. 这项研究优化了 (Sr1-xPrx) 0.95FeO3-δ,减少了热膨胀,改善了对称空气和燃料电极的氧化还原稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能和能源转化 储能和能源转化
背景情况:
- 基于铁氧化 (SrFeO3) 的电极对固体氧化物燃料电池 (SOFCs) 显示出了前景.
- 现有的挑战包括高热膨胀系数和有限的氧化还原稳定性.
- 兴奋剂策略对于改善SOFC电极性能至关重要.
研究的目的:
- 为了优化 (Sr1-xPrx) 0.95FeO3-δ材料,通过变化 (Pr) 含量.
- 评估 Pr 兴奋剂对热膨胀,氧化还原稳定性和电化学性能的影响.
- 评估这些材料作为SOFC中的对称空气和燃料电极的适用性.
主要方法:
- (Sr1-xPrx) 0.95FeO3-δ系列 (0 < x ≤ 1) 的合成和表征.
- 瑞特维尔德对X射线和中子衍射数据的改进,以确定晶体结构.
- 热重度测量分析 (TGA) 和扩度测量分析,以评估氧气非静态测量和热膨胀.
- 电化学阻抗光谱 (EIS) 用于测量电极极化电阻.
- 重氧循环测试以评估稳定性.
主要成果:
- 观察到的相位转换:四角形到立方 (0.2 ≤ x ≤ 0.4),然后到正角形 (x ≥ 0.6).
- 增加的 Pr 含量显著降低了热膨胀系数 (从 31 × 10−6 K−1 降至 8.4 × 10−6 K−1).
- 高电导率保持到x = 0.8 (700°C时为116 S cm−1).
- 实现了低电极极化电阻 (例如,在空气中为0.11 Ω cm2,在H2中为0.09 Ω cm2,x = 0.6).
- 证明了出色的氧化还原循环稳定性.
结论:
- (Sr1-xPrx) 0.95FeO3-δ材料的x≥0.6对SOFC电极是有希望的.
- 催化剂有效调整热膨胀和电化学性质.
- 这些材料为对称的SOFCs在氧化和还原环境中提供可靠的性能.
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