長寿命の電荷分離状態は,リガンドで安定した銀のクラスターにある
Matthew Pelton1, Yun Tang, Osman M Bakr
1Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA. pelton@anl.gov
Journal of the American Chemical Society
|July 11, 2012
まとめ
リガンドで安定した銀のクラスターは,レーザー刺激後,光学特性の迅速かつ遅い衰退を示しています. これらの崩壊は,溶媒の極性によって影響され,太陽エネルギー採集アプリケーションの可能性を示唆しています.
科学分野:
- ナノ材料科学 ナノ材料科学
- フォトケミストリー フォトケミストリー
- 物理化学 物理化学
背景:
- アロマティックチオールリガンドによって安定した原子単分散の銀のクラスターが合成されています.
- これらの星団は,可視光線と近赤外線スペクトルで強い吸収を示しています.
研究 の 目的:
- レーザー刺激後,これらの銀のクラスターの時間依存の光学特性を調査するために.
- 光学的な振る舞いを支配する運動過程を理解し,太陽エネルギーアプリケーションの潜在能力を評価する.
主な方法:
- 吸収ピークを越えた銀のクラスターの超高速レーザー刺激.
- 時間の解像度を持つ光学スペクトロスコピーは,崩壊運動を監視します.
- 動的プロセス依存性を研究するために,溶媒の極性変化.
主要な成果:
- 2つの異なる運動崩壊過程が観察されました:急速な崩壊 (<1 ps) と遅い崩壊 (>300 ns).
- 両方の分解時間定数は,溶媒の極性度が増加するにつれて減少した.
- これらのプロセスは,電荷分離状態の形成と再結合に起因する.
結論:
- リガンドで安定した銀のクラスターは,長寿命の電荷分離状態を示します.
- 彼らの広い光学吸収と長い状態の寿命は,太陽エネルギー採集の有望なものです.
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