ヘクサベンゾコロネンの高品質の分散は有機溶媒に含まれています
J Marguerite Hughes1, Yenny Hernandez, Damian Aherne
1School of Physics & CRANN, Trinity College Dublin, University of Dublin, Dublin 2, Ireland.
Journal of the American Chemical Society
|June 22, 2012
まとめ
溶媒におけるヘクサベンゾコロネン (HBC) の分散は,溶媒の性質に依存し,最適な濃度はヒルデブランド溶解度パラメータ21 MPa (((1/2)) の近くにある. 特定の溶媒は,集積物だけでなく,個々のHBC分子の高濃度を可能にします.
科学分野:
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
- 超分子化学 超分子化学
背景:
- ヘクサベンゾコロネン (HBC) は,有機電子学の潜在的な応用を持つディスク分子です.
- 様々な溶媒におけるHBCの溶解性および集積行動を理解することは,その処理と応用にとって極めて重要です.
- 溶媒の性質は,有機分子の分散と自己組織化に大きく影響する.
研究 の 目的:
- ヘクサベンゾコロネン (HBC) の剥離と分散を,幅広い溶媒で調査する.
- HBCの分散濃度と集積状態を溶媒特性,特にヒルデブランド溶解性パラメータと相関させる.
- HBC分散における個々の分子および総含有量を定量化するためのメトリックを確立する.
主な方法:
- 28種類の溶媒でのHBC分散の体系的な研究.
- 分子と積分の含有量を決定するために吸収と光発光スペクトルの分析.
- 分散特性とヒルデブランド溶解性パラメータの相関.
- スキャントンネル顕微鏡 (STM) と伝送電子顕微鏡 (TEM) を用いた自己組み立て構造物の特徴化.
主要な成果:
- HBCの分散濃度は,ヒルデブランド溶解度パラメータが21MPaに近い溶媒で最大化されます.
- サイクロヘキシルピロリドン (CHP) のような良い溶媒は,個々のHBC分子の高濃度を維持し,テトラヒドロフーラン (THF) のような貧弱な溶媒は,低濃度でも集積を促進します.
- HBCの集積は,アミド溶媒と比較して,ハロゲン溶媒におけるヒルデブランドパラメータに対してより敏感である.
- 4つの溶媒 (CHP,1-クロロナフタレン,1-ブロモナフタレン,1,2,4-トリクロロベンゼン) が特定され,個々のHBC分子の全体的な高濃度と大規模な集団の両方を可能にしました.
- STMとTEMは,自己組み立てモノレイヤーと,HBCモノマーまたは小さな集積物と一致するグラフィティックオブジェクトを発見しました.
結論:
- 溶媒の選択は,個々のHBC分子の高濃度を達成し,集積を制御するために重要です.
- ヒルデブランド溶解度パラメータが約21 MPa ((1/2) の溶媒は,HBC.を分散させるのに有望である.
- この発見は,溶液処理可能なHBCベースの材料を設計し,それに合わせた特性を備えるための基礎を提供します.
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