单临床Sr{1-x) Na{x) SiO{3-0.5x):新的高级氧化物离子电解质
Preetam Singh1, John B Goodenough
1Texas Material Institute and Materials Science and Engineering Program, The University of Texas at Austin, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|June 22, 2013
概括
用添加的酸电解质可以降低固体氧化物燃料电池的运行温度. 这些新材料在525°C时表现出高氧化离子导电性,这使得它们对中温应用具有前景.
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
- 陶制品 在陶方面.
背景情况:
- 氧化物离子电解质对于固体氧化物燃料电池 (SOFC),氧气分离膜和氧气传感器至关重要.
- 将工作温度从>800 °C降低到~500 °C是SOFCs降低成本和提高效率的关键目标.
研究的目的:
- 作为 (K+) 兴奋剂的替代品,对单临床石酸盐 (SrSiO3) 中的 (Na+) 兴奋剂进行调查.
- 为了提高中温SOFC应用的氧化物离子导电性和稳定性.
主要方法:
- Sr1-xNaxSiO3-0.5x固体溶液的合成和表征.
- 测量氧化物离子导电性 (σo) 作为温度的函数.
- 用典型的阳极和阴极材料评估材料的稳定性.
主要成果:
- 对于Sr1-xNaxSiO3-0.5x,相对于K+兴奋剂类似物,获得了更广泛的固体溶液范围 (0 < x ≤ 0.45).
- 在525°C时,氧化离子导电率 σo ≥ 10−2 S·cm−1 达到.
- 与Na+相合的电解质具有较低的湿透性,并且与Ni复合体阳极和常见的矿阴极具有良好的稳定性.
结论:
- 在SrSiO3中Na+兴奋剂有效降低过渡温度到完全氧化离子障碍,增强导电性.
- Sr1-xNaxSiO3-0.5x电解质由于其导电性和稳定性,是中温固体氧化物燃料电池的有希望的候选者.
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