トライブロックコポリマー助成合成による新しいIa-3d立方体メソ構造化シリカの形成
Katarina Flodström1, Viveka Alfredsson, Niklas Källrot
1Physical Chemistry 1, Lund University, P.O. Box 124, SE- 221 00 LUND, Sweden. katarina.flodstrom@fkem1.lu.se
Journal of the American Chemical Society
|April 10, 2003
まとめ
研究者は,大きな単位細胞と高い表面積を持つ新しいメソポラスシリカを合成しました. この新しい素材は立方軸対称性を表しており,潜在的にギロイドの最小表面に基づいている.
科学分野:
- マテリアルサイエンス 材料科学
- ナノテクノロジー ナノテクノロジー
- 化学 化学は化学です.
背景:
- メソポラスシリカ材料は,触媒と分離において極めて重要です.
- 制御された孔構造を持つ新しい構造の開発は,現在進行中の研究分野です.
- 既存の合成方法では,より小さな単位細胞を持つ構造がしばしば得られます.
研究 の 目的:
- 新しいメソポラスシリカ構造を合成し,特徴づけること.
- シンメトリーとユニット細胞の寸法を含む構造的性質を調査する.
- メソポラスシリカ合成におけるヨウ素塩の使用の可能性を調査する.
主な方法:
- トライブロックコポリマー (Pluronics P103またはP123) を用いて合成し,ヨウ素ナトリウム (NaI) を添加する.
- シンメトリを決定するために小角X線散射 (SAXS) を使用した特徴付け.
- 孔構造を明らかにするために電子マイクログラフの分析.
- ガス吸附技術を用いた表面積の決定.
主要な成果:
- 立方円対称性のメソポラスシリカの合成に成功しました.
- 非常に大きな単位細胞寸法 (合成した場合は250 Å,焼却した場合は222 Åまで) が観察されました.
- 約700 m2/gの大きな表面積を達成しました.
- MCM-48との構造的類似性が示唆され,ギロイドの最小表面を示しています.
結論:
- 合成混合物へのNaIの添加により,Iad対称性を持つ新しいメソポラスシリカの形成が可能になります.
- 合成された材料は,例外的に大きな単位細胞と高い表面積を持っています.
- 構造は,ジロイドの最小表面に基づいて設計され,素材デザインの新たな可能性を提供します.
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