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Updated: Mar 2, 2026

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

Published on: September 12, 2014

新しいボディピ派生体におけるラジカル・エンハンスド・インターシステム・クロッシングと効率的なトリプル・トリプル・アニヒレーション・アップコンバージョンの適用

Zhijia Wang¹, Jianzhang Zhao¹, Antonio Barbon²

¹State Key Laboratory of Fine Chemicals, Dalian University of Technology , E-208 West Campus, 2 Ling-Gong Road, Dalian 116024, People's Republic of China.

Journal of the American Chemical Society

|May 20, 2017

まとめ

研究者は,激素強化型インターシステムクロス (EISC) を使用して,ボロン二ピロメタン (Bodipy) で長寿のトリプル興奮状態を達成しました. この画期的な発見により,効率的なトリプル・トリプル・アニヒレーション・アップコンバージョンが可能になり,光化学の新たな道が開かれました.

科学分野:

写真化学
有機化学
スペクトロスコーピー

背景:

ボロン二ピロメタン (Bodipy) はよく知られているフッ素素である.
三重興奮状態は,光物理学的プロセスにおいて極めて重要です.
ラジカル・エンハンスド・インターシステム・クロス (EISC) はトリプル状態への経路を提供します.

研究の目的:

ボディピーの興奮状態を初めて観察し特徴づけました
ボディピー酸化窒素二酸化物におけるEISCのメカニズムを調査する.
トリプレット・トリプレット・アニヒライレーション (TTA) アップコンバーションにおけるEISCの応用を探求する.

主な方法:

異なるリンク長を持つボディピー-テンポダイアードの合成.
静止状態と時間解像度のトランジント光学スペクトルスコピー
連続波電子スピン共振 (cw-ESR) と時間解像度ESR (TR-ESR)

主要な成果:

効率的なEISC (Φ_T = 80%) と長いBodipyトリプル状態の寿命 (62 μs) は,より短いリンクヤーで達成されました.
TR-ESRは,ラジカルトリプルペアメカニズムでスピン偏振TEMPO信号を確認した.
EISCはTTAのアップコンバーションに成功し,量子収率は6.7%であった.

結論:

効率的なEISCと長いトリプル寿命は,柔軟なBodipy-nitroxideシステムで実証されました.
これは厳格なEISCシステムでの以前の発見と対照的です.
この研究は,TTAのアップコンバージョンアプリケーションにおけるEISCの可能性を明らかにしています.

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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

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