表面触媒反応の原子と顕微鏡の反応速度
Wintterlin1, Volkening, Janssens
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
Science (New York, N.Y.)
|December 24, 1997
まとめ
この研究ではスキャニングトンネル顕微鏡を用いて,プラチナ表面における一酸化炭素 (CO) の酸化を観察した. 原子レベルでのイメージングは反応運動を明らかにし,この触媒過程の新しい速度法則につながった.
科学分野:
- 表面科学とは,地表科学である.
- 化学動力学 化学動力学
- カタリシス カタリシス カタリシス
背景:
- 一酸化炭素 (CO) の触媒性酸化は,多くの産業プロセスにおいて極めて重要です.
- 原子レベルで表面反応を理解することは,触媒を最適化するための鍵です.
- プラチナ (111) は,CO酸化カタリシスのためによく研究された表面です.
研究 の 目的:
- プラチナ (111) 表面でのCOの触媒酸化を原子スケールで調査する.
- 吸収された酸素とCO分子間の反応ダイナミクスを監視するために.
- 反応物質の空間的分布に基づいた速度法則を開発する.
主な方法:
- スキャントンネル顕微鏡 (STM) が原子解像度のイメージングに使用されました.
- 吸収された酸素原子とCO分子が直接可視化されました.
- 反応の進行は,さまざまな温度で時間とともに監視されました.
主要な成果:
- 反応物質と産物の原子解像度画像作成が達成されました.
- 反応物質領域分布を考慮した新しい速度法則が策定された.
- 運動パラメータは,温度に依存する測定から決定されました.
- 取得した運動パラメータは,マクロスコーピカルデータと良好な一致を示した.
結論:
- Pt (111) 上のCO酸化の詳細な動的記述が確立されました.
- この研究は,原子レベルのプロセスを,マクロスケールの反応率と結びつけることに成功した.
- この研究は,表面触媒反応に関する基本的な洞察を提供します.
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