微孔性金属有機構造体 (コ ((1,4-ベンゼンディピラゾラート) において,広範囲にヒステリックなH2吸附
Hye Jin Choi1, Mircea Dincă, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|June 3, 2008
まとめ
新しい金属有機フレームワークは,柔軟な構造と高い表面積を示し,水素貯蔵の可能性を示しています. そのユニークな吸附特性とH2の拡散ダイナミクスを調査した.
科学分野:
- マテリアルサイエンス 材料科学
- 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,多孔性の結晶材料で,さまざまな用途があります.
- ガス貯蔵と分離のための特性を合わせたMOFの開発は,活発な研究分野です.
研究 の 目的:
- コバルトと新しいリガンドを用いた新しい金属有機構造を合成し,特徴づけること.
- 合成されたMOFの構造的,熱的,およびガス吸附特性を調査する.
- 水素貯蔵のためのこのMOFの潜在能力を探求し,H2拡散ダイナミクスを研究する.
主な方法:
- 溶熱反応による金属有機枠組Co(BDP).2DEF.H2Oの合成.
- 構造分析のためのX線 difraktion (XRD) と粉末XRD.
- 熱安定性および溶解解化の研究のための熱重力測定分析 (TGA).
- 窒素と高圧水素吸附イソテルムは,表面積とガス吸収を決定する.
- H2拡散分析のための可変温度動力学的測定.
主要な成果:
- 合成されたMOF,Co(BDP).2DEF.H2Oは,10x10 Åチャネルを持つ3Dフレームワークを形成する.
- フレームワークは高い熱安定性と柔軟性を示し,溶解/溶解時に可逆的に変換します.
- 窒素吸附により,高表面積 (2670 m2/g) と異例の5段階の吸附プロセスが明らかになった.
- 高圧H2吸附は,ヒステリックな吸収/放出を示し,容量は50Kで5.5%重量であった.
- MOF内のH2拡散が研究され,エネルギーバリアは0.62kJ/molであった.
結論:
- 新型MOFは,柔軟なフレームワークと有意な多孔性を持ち,水素貯蔵の有望な候補となります.
- 観測されたH2吸附行動は,ガス貯蔵における動的トラッピングメカニズムの可能性を示唆しています.
- この研究は,MOF内のH2拡散運動に関する最初の調査を提供し,ゲスト分子のダイナミクスに関する洞察を提供します.
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