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可視光を用いた金属表面での分子光解離への直接的経路
Emiko Kazuma1, Jaehoon Jung2, Hiromu Ueba3
1Surface and Interface Science Laboratory, RIKEN , Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|February 8, 2017
まとめ
目に見える光は 金属の表面の化学結合を断ち切る事ができました 以前は不可能と考えられていました 分子光解離のこの突破は インタフェースのユニークな電子相互作用によって引き起こされています
科学分野:
- 表面科学
- 写真化学
- 材料科学
背景:
- 金属基板での可視光誘導による分子光解離は困難です.
- 低光子エネルギーと分子金属混合による短い興奮状態の寿命は,このプロセスを妨げます.
研究 の 目的:
- 単結晶金属基板の可視光駆動分子光解離を実証し説明する.
- この現象を可能にするインタフェースの電子構造の役割を調査する.
主な方法:
- スキャントンネル顕微鏡を用いた実験調査.
- 密度関数理論による理論分析.
主要な成果:
- ダイメチル二酸化物におけるS−S結合は,Cu−""""とAg−""""を可視光で成功的に分離した.
- HOMO由来 (nS) から LUMO由来 (σ*SS) の分子軌道への直接的な電子刺激がメカニズムとして特定された.
- 分子と金属のハイブリッド化により,エネルギーギャップが減り,興奮状態の寿命が長くなり,光解離が容易になった.
結論:
- 金属表面での可視光誘発分子光解離は達成可能である.
- インタフェースの電子構造とハイブリッド化は,エネルギーレベルと興奮状態の寿命を調節することによって,このプロセスを可能にする上で重要な役割を果たします.
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