結晶構造,拡散経路,およびPr(2) NiO(4) ベースの混合導体 (Pr(0.9) La(0.1)) (((2) ((Ni(0.74) Cu(0.21) Ga(0.05)) O(4+デルタ) の酸素浸透性について
Masatomo Yashima1, Nuansaeng Sirikanda, Tatsumi Ishihara
1Department of Materials Science and Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-Ku, Yokohama, Kanagawa 226-8502, Japan. yashima@materia.titech.ac.jp
Journal of the American Chemical Society
|February 4, 2010
まとめ
この研究では,ドーピングされたプラセオジウムニッケル酸化物 (Pr0.9La0.1) 2 ((Ni0.74Cu0.21Ga0.05) O4+δ) が,効率的なイオン拡散経路により,優れた酸素浸透性を示すことが明らかになりました. その低い活性化エネルギーは,酸素分離アプリケーションにおける高性能の可能性を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- オキシードイオン導体 オキシードイオン導体
背景:
- プラセオジウムニッケル酸化物は,酸素分離のための有望な混合導体である.
- 結晶構造とイオン拡散を理解することは,パフォーマンスを最適化するために重要です.
研究 の 目的:
- 特定のドーピングされたプラゼオジミウムニッケル酸化物 (Pr0.9La0.1) 2 ((Ni0.74Cu0.21Ga0.05) O4+δ (PLNCG)) のインシット結晶構造,酸素拡散,浸透率,伝導性を調査する.
- 酸素拡散機構とその物質特性との関係を解明する.
主な方法:
- 空気中の広い温度範囲 (271015.6 °C) にわたるPLNCGの性質の現地調査.
- 中性子とシンクロトロン difraktion,リートヴェルド精錬,最大エントロピー法 (MEM),および理論的な計算を活用しました.
- 電子密度マップと最も高い分子軌道 (HOMO) を分析し,結合と伝導を理解した.
主要な成果:
- PLNCGは,2D共振性Ni-Oネットワークを備えた四角形のK(2) NiF(4) 型構造を維持しています.
- 大量酸素浸透率 (1000 °Cで137 μmol cm−2 min−1) と低活性エネルギー (950 °Cで51 kJ mol−1) を達成した.
- 大量オキシドイオン拡散の鍵となるインタースティシャルO3とアニソトロピックアピカルO2サイトを特定し,高温で拡散経路が強化される.
結論:
- 調査されたドーピングされたプラセオジウムニッケル酸化物は,特定の大量拡散経路によって誘導される効率的な酸素浸透を示しています.
- 酸素浸透の低活性化エネルギーは,酸素分離技術,特に高品質の単結晶または薄膜でのアプリケーションの有意な可能性を示唆しています.
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