黄金とプラチナの表面における窒素電気化学的還元反応に関するスペクトロスコピック研究
Yao Yao1,2, Shangqian Zhu1,2, Haijiang Wang1,2
1Department of Chemical and Biological Engineering, and ‡Energy Institute, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
Journal of the American Chemical Society
|January 11, 2018
まとめ
黄金 (Au) 触媒での窒素のアンモニアへの電気化学的還元は,窒素-水素の種を検出した関連メカニズムに従います. この発見は,プラチナ (Pt) 触媒とは異なり,反応経路を明確にします.
科学分野:
- 電気化学
- カタリシス
- 表面科学
背景:
- 電気化学的窒素をアンモニアに還元することは持続可能なエネルギー変換プロセスです.
- 反応メカニズムと中間物質を理解することは,触媒の性能を最適化するために不可欠です.
- 金基の触媒は可能性を示しているが,反応経路は不明である.
研究 の 目的:
- 黄金の表面で窒素をアンモニアに還元する反応機構を解明する.
- 内部スペクトロスコーピーを用いて重要な反応中間物質を特定する.
- 金とプラチナの反応経路を 比較するためです
主な方法:
- 表面強化赤外線吸収光学 (SEIRAS) がインシット分析に使用された.
- 窒素還元は金色の薄膜電極で実施された.
- 電気化学的電位は,可逆水素電極に対して制御された.
主要な成果:
- 窒素-水素 (N2Hy) 種が0V未満のゴールド表面で検出されました.
- 特徴的な振動帯 (1453,1298,1109 cm−1) は,N−2−H−y−中介物質を確認した.
- 同じ条件下でプラチナに窒素を含む中間物質は観察されなかった.
結論:
- 黄金に対する窒素還元反応は,結合的メカニズムを経由する.
- NN結合は水素添加とともに断ち切られる.
- このメカニズムは,水素の進化が支配する窒素の減少のためのプラチナと比較して,金のより高い効率を説明します.
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