モノクリニックSr{1-x) Na{x) SiO{3-0.5x):新しい上位酸化イオン電解質
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
まとめ
ナトリウムドーピングされたストロンチウムシリケート電解質は,固体酸化物燃料電池のより低い動作温度を可能にします. これらの新しい材料は,525°Cでの高オキシドイオン伝導性を示し,中等温度の用途に有望である.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- 陶器はセラミックです.
背景:
- オキシードイオン電解質は,固体酸化物燃料電池 (SOFC),酸素分離膜,酸素センサーに不可欠です.
- 作業温度を>800 °Cから~500 °Cに低下させることは,SOFCがコストを削減し,効率を向上させるための重要な目標です.
研究 の 目的:
- カリウム (K+) ドーピングの代替品として,モノクリン性ストロンチウムシリケート (SrSiO3) のナトリウム (Na+) ドーピングを調査する.
- オキシドイオン伝導性と安定性を向上させ,中温度のSOFCアプリケーションに使用します.
主な方法:
- Sr1-xNaxSiO3-0.5x固体溶液の合成と特徴づけについて.
- 温度関数として酸化イオン伝導率 (σo) の測定.
- 典型的なアノドおよびカトド材料による材料の安定性の評価.
主要な成果:
- Sr1-xNaxSiO3-0.5xは,K+ドーピングされた類似体と比較して,より広い固体溶液範囲 (0 < x ≤ 0.45) を達成しました.
- 525 °Cで σo ≥ 10−2 S·cm−1 の酸化イオン伝導度に達した.
- Na+ドーピングされた電解質は,Ni-複合性アノドと一般的なペロブスキートカトドとの比較では低微視性と良好な安定性を示した.
結論:
- SrSiO3にNa+ドーピングを施すと,完全な酸化イオン障害への移行温度が効果的に低下し,伝導性が向上します.
- Sr1-xNaxSiO3-0.5x電解質は,導電性と安定性により,中温固体酸化物燃料電池の有望な候補である.
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