微孔性金属有機構造体Mn3 (Mn4Cl) 3 (BTT) 8 (CH3OH) 10のカタオン交換変種における高エンタルピー水素吸収2
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 21, 2007
まとめ
新しい金属有機フレームワークは,高い水素貯蔵能力を示しています. イオン交換により,調節可能なH2結合を持つ材料が生成され,コバルト交換化合物は,微孔のフレームワークで記録的な吸収エンタルピーを示します.
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,ガス貯蔵アプリケーションに有望である.
- マイクロ孔性のMOFは,吸収のための大きな表面積を提供します.
- MOFプロパティのチューニングは,パフォーマンスを最適化するための鍵です.
研究 の 目的:
- カチオン交換による新しい同構造MOFの合成と特徴付け.
- これらの新材料の水素 (H2) 貯蔵能力を評価する.
- MOF構造内のH2結合相互作用を調査する.
主な方法:
- Mn3[(Mn4Cl) 3(BTT) 8(CH3OH) [10]2でMn2+を用いたイオン交換反応は,様々な金属カチオン (Li+, Cu+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+) を含む.
- 溶解安定性試験について.
- 低温 (77K) H2吸附測定 900トロールで実施しました.
- ゼロカバーでのアドソルプション測定のイソステリック熱.
主要な成果:
- 溶解まで安定した同構造枠組化合物 (1-M) の形成.
- 高 H2 貯蔵容量は 2.00 から 2.29 wt % に及ぶ.
- H2結合強度の変動 (2 kJ/molの差) は,金属中心の相互作用に起因する.
- コバルト交換化合物 (1-Co2+) は,微孔性MOFに対して,アドソルプションの初期エンタルピー (10.5kJ/mol) が最高であった.
結論:
- カチオン交換は,H2貯蔵のための調節可能で安定したMOFを作成するための効果的な方法です.
- 観測されたH2結合エンタルピーは,不飽和金属中心との相互作用と相関しています.
- Co2+交換されたMOFは,この材料クラスにおけるH2吸収の新たな基準となる.
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