自己組み立てた単純な六角形AB (((2) 二進ナノクリスタル超格子:SEM,GISAXS,および欠陥
Danielle K Smith1, Brian Goodfellow, Detlef-M Smilgies
1Department of Chemical Engineering, Texas Materials Institute, Center for Nano- and Molecular Science and Technology, The University of Texas at Austin, Austin, Texas 78712-1062, USA.
Journal of the American Chemical Society
|February 17, 2009
まとめ
鉄酸化物と金ナノ結晶から成るバイナリースーパーラット (BSL) が成功裏に組み立てられました. これらの構造は,単純な六角形AB(2) の配置を示し,堆積時に格子収縮と対称性の変化が観察されています.
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
- クリスタログラフィーです.
背景:
- バイナリースーパーグリット (BSL) は,異なるサイズのナノ粒子の制御された配置を通じて調節可能な性質を提供します.
- ナノ結晶の自己組み立ては,オーダーされたナノ材料を作成するための重要な戦略です.
- BSLの構造的なニュアンスを理解することは,その適用に不可欠です.
研究 の 目的:
- 鉄酸化物と金ナノ結晶のバイナリ超格子 (BSL) を組み立て,特徴づけること.
- 組み立てられたBSLの構造的順序と対称性を明らかにする.
- 基板の相互作用と乾燥がBSL構造に及ぼす影響を調査する.
主な方法:
- 傾いた基板にコロイド分散物の緩やかな蒸発.
- 構造分析のための伝送電子顕微鏡 (TEM) とスキャニング電子顕微鏡 (SEM).
- 牧草発生小角X線散射 (GISAXS) は,長距離の秩序と構造パラメータを測定する.
主要な成果:
- シンプルな六角形 (sh) AB(2) のバイナリ・スーパーラットスの組立 (AlB(2)).
- 遠距離順序の確認とナノ結晶の配置の識別 (グリットで大きなFe(2) O(3),インタースティシャルサイトで小さなAu).
- 溶剤の乾燥による基板に垂直に超網膜の収縮 (8-12%) を観察し, (100) 面に中心のオーソロンビック対称性をもたらした.
- 挿入された金ナノ結晶半平面から成る超格子変位の識別.
結論:
- Fe(2) O(3) とAuナノ結晶のBSLは,オーダーされたsh-AB(2) 構造に組み立てることができます.
- 溶媒の乾燥により,構造的収縮と対称性の変化が顕著に起こります.
- この研究は,ナノ結晶超の自己組み立てメカニズムと構造的安定性についての洞察を提供します.
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