リガンドを中心とした光触媒式水素生成 (赤色照明による軸上Rh2)
Matthew T Fortunato1, Curtis E Moore1, Claudia Turro1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43214, United States.
Journal of the American Chemical Society
|December 6, 2023
まとめ
bpnpリガンドを含む新しいロジウム複合体が合成された. 複合体4は,この種の反応で初めて,リガンド中心の光触媒H2生成を示した.
科学分野:
- 協調化学
- 光触媒
- 材料科学
背景:
- ロジウム (II,II) ダイマーは,独自の電子構造と触媒能力で知られています.
- リガンドの設計は,金属複合体の性質と反応性を調整するために不可欠です.
- 金属-リガンドの相互作用を理解することは,効率的な光触媒の開発の鍵です.
研究 の 目的:
- 異なる軸結合体を持つロジウム (II,II) 複合体の新しいシリーズを合成し,特徴づけること.
- これらの複合体の光物理的性質と電気化学的振る舞いを調査する.
- 光触媒による水素生成の可能性を 探求するためです
主な方法:
- cis-[Rh2{DTolF) 2{bpnp}{L) ]2+複合体の合成 (L = pdz, cinn, bncn)
- 還元ポテンシャルを決定するための電気化学分析 (サイクル電圧計)
- 電子トランジションを研究するためのUV-Vis吸収スペクトル.
- 光触媒実験は,犠牲の減少剤と酸の存在で可視光照射を使用します.
主要な成果:
- 合成されたロジウム複合体は,異なる金属/リガンド対リガンド電荷伝達帯 (ML-LCT) を表している.
- ベンゾ[c]シナリン (bncn) リガンドを含む複合体4は,H2生成のための光触媒活性を示した.
- 特殊な条件下で,複合体4を用いてH2の生産を16回達成した.
- bpnpリガンドの軸性キャピングは,bncnリガンドの反応を局限化して,Rh-Hヒドリドの形成を防止した.
結論:
- この研究は,調節可能な光物理的性質を持つ新しいロジウム (II,II) 複合体を提示する.
- 複合体4のベンゾ[c]シナリンリガンドは,光触媒的なH2生成の活性部位として特定されています.
- この研究は,ロジウム二金属系におけるリガンド中心のH2生成の最初の例を示している.
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