ナノ粒子の大きさの関数としての選択性は,不飽和アルコールの触媒性水素化における
Somnath Bhattacharjee1, David M Dotzauer, Merlin L Bruening
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Journal of the American Chemical Society
|February 24, 2009
まとめ
触媒ナノ粒子のサイズは,水素化の選択性に劇的な影響を及ぼします. 小さいパラジウムナノ粒子は,単位置換不飽和アルコールに対する選択性を高め,大きいものは多位置換化合物を好む.
科学分野:
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
- ナノテクノロジー ナノテクノロジー
背景:
- 効率的で選択的な触媒の開発は,化学合成に不可欠です.
- ナノ粒子のサイズを制御することは,触媒特性を調節する鍵です.
研究 の 目的:
- ポリエレクトロライトフィルムに埋め込まれたパラジウム (Pd) ナノ粒子触媒を合成するために.
- 水素化反応の触媒的選択性に対するPdナノ粒子の大きさの影響を調査する.
主な方法:
- ポリ・アクリル酸) -Pd・II) コンプレックスとポリ・エチレニミン) をアルミニウムに層ごとに吸収する.
- NaBHを用いることで,Pd (II) をPdナノ粒子に還元する (4).
- ナノ粒子のサイズ (2.23.4 nm) を制御するために,ポリアクリル酸 (Pd) とPd (II) の比率を変更します.
主要な成果:
- 触媒的選択性は,Pdナノ粒子のサイズによって有意に変化した.
- モノ置換不飽和アルコールのターンオーバー周波数 (TOF) は,ナノ粒子のサイズが減少するにつれて増加しました.
- 多複置換不飽和アルコールのTOFは,ナノ粒子サイズが大きくなるにつれて増加し,逆の傾向を示した.
結論:
- より小さなPdナノ粒子は,単位置換不飽和アルコールを水素化するための選択性が高くなります.
- より大きなPdナノ粒子は,多置換不飽和アルコールに対してより選択的です.
- ナノ粒子のサイズに依存する選択性は,基板結合のための活性部位の可用性に関連付けられています.
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