硫化金属有機枠の酸性に対する三次元的に秩序付けられた欠陥サブレットの役割
Jared M Taylor1,2, Tokutaro Komatsu1, Shun Dekura1
1Division of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|August 25, 2015
まとめ
メタル・オーガニック・フレームワーク (MOF) の結晶欠陥の衝撃特性 この研究では,燃料電池アプリケーションに不可欠な高プロトン伝導性を達成するために,ジルコニウム2硫黄フェタル酸MOFの欠陥を最適化しました.
科学分野:
- 材料科学
- 化学について
- ナノテクノロジー
背景:
- 結晶の欠陥は固体材料の特性に大きな影響を与える.
- メタル・オーガニック・フレームワーク (MOF) は,様々な用途のためのユニークな構造を提供します.
- 亜硫酸ジルコニウムMOFは,その物理的特性に影響を与える部分的に占有されている場所を持っています.
研究 の 目的:
- ジルコニウム2硫黄フェタラートMOFの結晶欠陥の役割を調査する.
- これらの欠陥が 陽子の伝導性にどう影響するかを理解するために
- プロトンの伝導性を高めるためにMOF構造を最適化します.
主な方法:
- 窒素ガスの吸い込みと微孔分析により,孔の大きさの分布を特徴付けます.
- プロトンの伝導性を測定するためにACインペデンス分析.
- 陽子の溶解エネルギーを決定する密度関数理論 (DFT) の計算.
主要な成果:
- 部分的に占有されたリガンド部位は,孔の大きさの連続を作り出します.
- 欠陥のあるジルコニウムクラスターは 陽子捕獲部として作用し 導電性に影響します
- クラスターpKaの最適化と酸の飽和は 陽子の伝導性を5倍にしました
結論:
- MOFの欠陥工学は物理的性質を調整する実行可能な戦略です.
- 適切な条件下で高い陽子伝導率 (5.62 × 10(-3) S cm(-1)) を達成した.
- 燃料電池のような陽子伝導アプリケーションでMOFの潜在能力を実証した.
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