アモニアトリボラン:新しい合成,構造的決定,および水溶性水素放出特性
Chang Won Yoon1, Patrick J Carroll, Larry G Sneddon
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|December 17, 2008
まとめ
アモニアトリボラン (NH3B3H7) は安全に作製でき,二水素結合により非対称な固体構造を示している. その水溶液は,移行金属触媒で素早く水素を放出します.
科学分野:
- 無機化学 無機化学とは
- マテリアルサイエンス 材料科学
- コンピューティング・ケミストリー
背景:
- ボーランは,水素貯蔵における潜在的な応用があるボロン-水素化合物のクラスです.
- アモニアトリボラン (NH 3 B 3 H 7) の合成と特徴づけは,その性質の探求に極めて重要です.
- アモニアトリボランの構造と反応性の側面を理解することは,その実用的な利用の鍵です.
研究 の 目的:
- アモニアトリボラン (NH 3 B 3 H 7) の安全かつ便利な製造方法の開発.
- X線結晶学とDFT計算を用いて,アンモニアトリボランとその添加物の固体構造を調査する.
- 水性アンモニアトリボラン溶液の水素放出特性を研究するために.
主な方法:
- アモニアトリボランの合成は,B(3) H(8) ((-) のヨウ素酸化を経て,アモニアの移転が続く.
- NH ((3) B ((3) H ((7) の固体構造とその18冠-6アダクトを決定するためのX線結晶学.
- 分子構造と結合を分析するための密度関数理論 (DFT) 計算.
- 水素の放出を測定するために,酸または移行金属触媒 (Rh/Al(2) O(3)) を用いた水解反応の研究.
主要な成果:
- アモニアトリボラン (NH 3 B 3 H 7) の安全で便利な製剤が確立されました.
- X線結晶学とDFTの研究は,対称性の計算上の予測に反して,分子間N-H-+...H-B二水素結合によって駆動されるNH(3) B(3) H(7) の高度に非対称な固体構造を明らかにしました.
- アモニアトリボランの水溶液は,酸またはRh/Al(2) O(3) 触媒を加えると素早く水素を放出し,特定の条件下で6.1%重量%のH(2) 放出を達成します.
結論:
- アンモニアトリボラン (NH 3 B 3 H 7 H) は,新しい方法を使用して効果的に合成することができます.
- アモニアトリボランの固体構造は,分子間二水素結合によって著しく影響を受け,非対称性が生じます.
- トリボランアンモニアは有望な水素貯蔵材料で,触媒によって促進される制御可能な水素放出率を持っています.
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