表面国家は,ナノ結晶-アセンの複合システムで三重エネルギー転送を媒介する
Jon A Bender1, Emily K Raulerson1, Xin Li2
1Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States.
Journal of the American Chemical Society
|May 31, 2018
まとめ
ハイブリッド材料におけるフォトンの向上変換は,効率的なエネルギー転送に依存しています. PbSナノ結晶の表面は 中間状態を形成し この重要なエネルギー伝達プロセスを中介し 時には阻害します
科学分野:
- 材料科学
- ナノテクノロジー
- 写真化学
背景:
- 半導体ナノ結晶 (NC) とアセンのリガンドを持つ混合有機:無機材料は,光子向上変換の有望性を示しています.
- フォトンのアップコンバージョンは,NCによって赤外線光を吸収し,その後,可視光を生成するアセンのエネルギー転送を含みます.
- NCとアセンの間の精密なエネルギー伝達のメカニズムはよく理解されていません.
研究 の 目的:
- TIPS-ペンタセンのリガンドで機能化されたPbSNCの興奮電子ダイナミクスを調査する.
- ナノ粒子におけるエネルギー伝達のメカニズムの解明:光子向上変換のためのアセンのシステム.
- エネルギー転送を媒介するNC表面の役割を理解する.
主な方法:
- TIPS- ペンタセンのリガンドを用いたPbSNCを研究するために,超高速の一時吸収スペクトロスコーピーを用いた.
- 制限された密度関数理論 (DFT) の計算が採用された.
- 暫定的な吸収線形とDFTの結果の分析は相関していた.
主要な成果:
- PbS NCの光刺激は,TIPS-pentaceneへのトリプルエネルギー転送を直接もたらさない.
- TIPS - ペンタセンのトリプルエクシトンを生成する前に,40 ps以内の中間状態が形成され,約100 ns持続する.
- この中間物質は,PbS NCの表面に位置する電荷キャリアであり,DFTは,エネルギー転送の促進器または罠として機能する多数のスピントリプル状態を明らかにします.
結論:
- PbS NC表面はアクティブにアセンのリガンドへのエネルギー転送を媒介する.
- NCの表面状態は,エネルギー転送を妨げるだけでなく,容易にすることができます.
- フォトンのアップコンバージョンやその他のアプリケーションのためのNCベースの材料を最適化するには,NC表面特性を注意深く検討する必要があります.
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