層層のシリケート表面活性物質のメソフェーズで分子的に秩序付けられた無機構造体
S C Christiansen1, D Zhao, M T Janicke
1Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|July 18, 2001
まとめ
研究者らは,カチオンの表面活性物質を用いて,結晶のような順序を持つ新種のシリカ表面活性物質複合物を合成した. 自己組み立てによって形成されたこれらの秩序ある無機構造は,材料科学における重要な進歩を表しています.
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:
- 自己組み立ては,オーダーされた材料を作成する上で重要なプロセスです.
- シリカ表面活性物質の複合材料は,さまざまな用途のために調節可能な性質を提供します.
- 構造指向剤を用いた秩序ある無機構造の直接合成は難しい.
研究 の 目的:
- 結晶のようなオーダーリングで自己組み立てたラメラーシリカ表面活性メソファース複合物を合成する.
- オーダーされた無機構造の形成を指揮するカチオンの表面活性物質の役割を調査する.
- 合成材料の分子組織と構造特性を特徴付ける.
主な方法:
- シリカ表面活性物質複合物の水熱合成.
- 様々なカチオンの表面活性剤の種を使用しています.
- 1Dおよび2D固体型NMRスペクトロスコーピー (29Si,ヘテロ核,ホモ核) を使用した特徴付け.
- X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD)) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD)) と赤外線 (IR) のスペクトロスコピーは,X線 difrraction (XRD) と赤外線スペクトロスコピーは,X線スペクトロスコピーは,
主要な成果:
- 結晶のようなオーダーリングで,ラメラーシリカ表面活性剤メソファース複合体を成功裏に準備しました.
- 構造を指示する表面活性物質を使用して,メソスコピカルにオーダーされた複合材料の直接合成を実証しました.
- アモルフなシリカから高度に秩序付けられたシリケートシート (2D結晶) への進行が観察されました.
- 表面活性物質の構造と形成速度が表面活性物質のヘッドグループ電荷密度に強く依存していることが判明した.
- NMRによるシリカフレームワークと表面活性物質の分子間の分子的近接が確認されました.
結論:
- カチオンの表面活性剤は,高度に秩序付けられた2D結晶シリケートシートの形成を効果的に導きます.
- 表面活性物質のヘッドグループにおける電荷密度は,構造と形成運動を制御する上で極めて重要です.
- これらのオーダーされたシリカ表面活性物質複合材料は,高度な応用の可能性のある新しい材料のクラスを表しています.
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