Pt(110) のin situ酸化研究と,COとの相互作用に関する研究
Derek R Butcher1, Michael E Grass, Zhenhua Zeng
1Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|November 11, 2011
まとめ
プラチナ (((110) の表面が酸素にさらされると,プラチナナノ粒子の表面酸化物と同じような表面酸化物が形成されます. 一酸化炭素は,化学的に吸収された酸素と表面酸化物の両方を除去し,触媒過程の洞察を提供します.
科学分野:
- 表面科学とは,地表科学のことである.
- カタリシス カタリシス カタリシス
- マテリアルサイエンス 材料科学
背景:
- プラチナ (Pt) 触媒は,多くの産業プロセスにおいて極めて重要です.
- Ptの表面構造を理解することは,触媒活動を最適化するための鍵です.
- オープン Pt 表面は,Pt ナノ粒子の触媒と類似性を共有しています.
研究 の 目的:
- O(2) に曝露されたPt(110) に形成された構造を調べる.
- これらの構造の安定性とCOに対する反応性を決定する.
- Ptナノ粒子触媒の触媒プロセスに関する発見を関連付けます.
主な方法:
- 環境圧力X線光電子スペクトロスコーピー (AP-XPS).
- 高圧スキャニングトンネル顕微鏡 (HP-STM).
- 密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.
主要な成果:
- 低O2圧では,化学的に吸収された酸素のみが観察される.
- 0.5 Torr O2で,多層のα-PtO2のような表面酸化物の島が形成されます.
- COは270Kで,化学的に吸収された酸素と表面酸化物を除去します.
結論:
- Pt(110) の表面酸化物構造は,Ptナノ粒子の表面酸化物構造に似ている.
- COの反応性は,開いたPt表面の触媒機構の洞察を提供します.
- 高圧下でのモデル触媒の現地試験は貴重なものです.
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