オープンアイアン (II) コーディネーションサイトを備えたリドックス活性金属有機枠組で,O2をN2に選択的に結合させる
Eric D Bloch1, Leslie J Murray, Wendy L Queen
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 12, 2011
まとめ
この研究は,選択的に酸素を吸収する能力を持つ新しい金属有機構造体Fe ((2) ((dobdc) を提示しています. この材料は,より高い温度で効率的な空気分離に有望であることが示されています.
科学分野:
- マテリアルサイエンス 材料科学
- 無機化学 無機化学とは
- 分離科学とは,分離科学である.
背景:
- メタル・オーガニック・フレームワーク (MOF) は,ガス吸附のための調整可能な特性を提供します.
- MOF-74/CPO-27タイプの構造は,高い表面積とチャネル状の毛穴で知られている.
- 酸素を空気から効率的に分離することは,様々な産業用途において極めて重要です.
研究 の 目的:
- 新しいFe (((2) ((dobdc) 金属-有機のフレームワークを合成し,特徴づけること.
- 溶解したフレームのガス吸附特性,特にO2とN2について調査する.
- 空気分離アプリケーションにおけるFe(2)(dobdc) の可能性を調査する.
主な方法:
- FeCl2とH4を用い,Fe(2)(dobdc) ·4DMFの空気のない合成.
- 溶解により,多孔性のFe(2)(dobdc) 物質が得られる.
- 298 K と 211 K のガス吸附イソサーム測定.
- 構造的および電子的特徴化のための光譜分析 (Mössbauer, IR) と粉末中性子 difraktion.
- 突破曲線のための理想的吸収溶液理論 (IAST) シミュレーション.
主要な成果:
- Fe (((2) (((dobdc) は,1360 m (((2) /gのBET表面積を持つMOF-74/CPO-27アナログとして合成されました.
- 材料は,高容量 (298 Kで9.3 wt%,211 Kで18.2 wt%) で,N(2) よりも選択的なO(2) 吸収を示しています.
- スペクトル学および difraktion データは,Fe (II) とO (II) の間の電荷の移転を示し,室温での酸化時にFe (III) とO (II) とO (II) を形成します.
- O(2) 結合モードは,低温で対称なサイドオンとして識別され,酸化時にサイドオンに滑り込みました.
結論:
- Fe (((2) (((dobdc) は,選択的酸素捕獲のための非常に効果的な材料です.
- 観測された可逆性O2吸附と電荷移転機構は,その性能の鍵となる.
- IASTのシミュレーションによると,Fe2 (dobdc) は高温での産業用空気分離の有望な候補である.
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