シングルサイト Pt1/CeO2カタリストに対するメタノール分解のメカニズム:A DRIFTS研究
Zhiyuan Qi, Luning Chen, Shuchen Zhang
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|December 28, 2020
まとめ
セリア (Pt1/CeO2) の単位プラチナはメタノールの分解活性が著しく高い. メタノールから作られる
科学分野:
- 異質な触媒
- 表面科学
- ナノ材料
背景:
- シングルサイト触媒は最大限の原子利用とユニークな性能を提供します.
- 以前の研究では,Pt1/CeO2は,メタノール分解のPtナノ粒子よりも40倍活性であることが示されました.
- この増強の分子のレベルでの理解は 以前には欠けていました
研究 の 目的:
- シングルサイト Pt1/CeO2でのメタノール分解の反応機構を調査する.
- 分子レベルでの反応経路を提案する.
- 触媒活性を増大させる要因を明らかにする.
主な方法:
- インサイト分散反射赤外線フーリエ変換スペクトロスコーピー (DRIFTS) が使用された.
- 反応経路を理解するために,運動分析と計算モデルが利用されました.
主要な成果:
- メタノールはナノセリアの支柱に 分離的に吸収される.
- メトキシ種は脱水化のために単一のPtサイトに拡散する.
- 薄結合した一酸化炭素 (CO) が産物として形成されます.
結論:
- Pt1/CeO2の活性化は,セリアの基板にメタノールの吸収が容易であることに起因する.
- メタルサポートの相互作用は,単一のPtサイトの電子特性を調整します.
- これらの要因は,メタノール分解の優れた性能に貢献します.
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