分子的に並べられたエチレン群を持つ二機能ハイブリッドメソポラス有機アルミノシリケート
Yongde Xia1, Wenxin Wang, Robert Mokaya
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
Journal of the American Chemical Society
|January 13, 2005
まとめ
私たちは,エチレンを含む新型のハイブリッドメソポラス有機アルミニオシリケート材料を合成し,水熱安定性を高めました. これらの材料は,分子的にオーダーされた孔壁と,高度なアプリケーションのための二機能特性を特徴としています.
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
- ナノテクノロジー ナノテクノロジー
背景:
- ハイブリッドメソポラス材料は,さまざまな用途にチューニング可能な性質を提供します.
- オルガノアルミノシリケートは,有機および無機成分の利点を組み合わせています.
- 水熱安定性の向上は,実用的な材料の使用に不可欠です.
研究 の 目的:
- 新しいエチレンを含むハイブリッドメソポラス有機アルミシリケート材料を合成し,特徴づけること.
- これらの材料の構造的秩序,多孔性,および熱安定性を調査する.
- エチレンの組み込みが水熱安定性や材料の機能性に与える影響を評価する.
主な方法:
- 1,2-bis(triethoxysilyl) エチレン (BTEE) をオルガノシリカ前駆体とイソプロポキシドアルミニウムとして合成.
- 粉末X線 difraktion,固体NMR ((29) Si, (13) C MAS NMR),およびラマン光譜を用いた特徴付け.
- 沸騰する水中の表面積,孔積,熱安定性,水熱安定性の評価.
主要な成果:
- 表面積 (>1300 m(2) /g) と孔積 (>1.10 cm(3) /g) が高く,結晶状で構造的に順番が整った材料を成功して合成しました.
- フレームワーク内で分子的に秩序付けられたエチレン群の存在が確認され,最大300°Cまで安定しています.
- エチレンの組み込みにより,オルガノシリカとオルガノアルミシリケート材料の両方の沸騰する水における強化された熱水安定性が実証されています.
- テトラエドールで調整されたAlとオーダーされたエチレン群から生じるオルガノアルミノシリケート材料の二機能特性を特定しました.
結論:
- エチレンをハイブリッドメソポラス有機アルミニウムシリケートに組み込むことは,構造的順序を改善し,熱水安定性を高めます.
- 合成された材料は望ましい多孔性と熱安定性を発揮し,要求の高いアプリケーションに適しています.
- これらの材料の二機能性は,ルイス酸の部位と特定の有機機能の両方を要求する触媒と吸収プロセスの道を開く.
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