水素を微細な金属有機構造で貯蔵し,Mn2+の調整部位が露出している
Mircea Dincă1, Anne Dailly, Yun Liu
1Department of Chemistry, University of California-Berkeley, Berkeley, CA 94720, USA.
Journal of the American Chemical Society
|December 21, 2006
まとめ
1,3,5-ベンゼネトリステトラゾラート (BTT3-) リガンドを使用した新しい多孔金属有機構造は,高い水素吸収と貯蔵密度を示しています. この材料は,MOFの吸着熱が最高で,効率的な水素貯蔵に不可欠です.
科学分野:
- 材料科学 材料科学とは
- 化学 化学は化学です.
- ナノテクノロジー ナノテクノロジー
背景:
- メタル・オーガニック・フレームワーク (MOF) は,ガス貯蔵アプリケーションに有望である.
- 高い表面積と特定の結合部位を持つMOFの開発は,効率的な水素貯蔵に不可欠です.
研究 の 目的:
- トリトピック・ブリッジング・リガンドを用いて,新しい多孔性金属・有機構造体を合成し,特徴づけること.
- 新しいMOFの水素貯蔵容量と吸収特性を評価する.
主な方法:
- 1,3,5-ベンゼネトリステトラゾラート (BTT3-) リガンドを用いた新しいMOFの合成.
- X線微分と中性子粉微分を用いた特徴化.
- 水素吸収の測定は,冷凍温度と高圧で実施した.
主要な成果:
- 独特の立方形のトポロジーを持つ多孔なMOFの形成: [Mn(DMF) [6]3[(Mn4Cl) 3(BTT) 8(H2O) [12]2.42DMF.11H2O.20CH3OH.
- 77Kと90barで6.9%の総H2吸収を達成し,液体水素貯蔵密度の85%に達しました.
- 最大同位体吸附熱は10.1 kJ/molであり,MONFの最高値であり,Mn2+部位でのH2結合に関連している.
結論:
- 合成されたMOFは,例外的な水素貯蔵能力を示しています.
- 吸着の高熱は,強力な相互作用を示唆し,実際的な水素貯蔵アプリケーションに有益です.
- 独特の立方体トポロジーと結合部位は,素材の優れた性能に貢献しています.
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