支持されたPt触媒に対するCO酸化と水ガスシフトにおける活性部位の特定
Kunlun Ding1, Ahmet Gulec2, Alexis M Johnson1
1Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
Science (New York, N.Y.)
|September 5, 2015
まとめ
プラチナの単一の原子は,CO酸化または水-ガスシフトの活性触媒サイトではありません. 赤外線スペクトロスコピーはナノ粒子から単一のプラチナ原子を区別することができ,プラチナナノ粒子が活性部位であることを明らかにします.
科学分野:
- カタリシス
- 材料科学
- スペクトロスコーピー
背景:
- 効率的な異質な触媒を設計するには,触媒活性部位を理解することが不可欠です.
- 最近の研究では,プラチナ (Pt) の単一の原子が非常に活発な触媒部位である可能性があることを示唆しています.
研究 の 目的:
- 赤外線光譜を用いてナノ粒子からプラチナの単一の原子を直接区別し,定量化する.
- CO酸化と水-ガスシフト反応におけるナノ粒子に対するプラチナ単一の原子の触媒的活性を調べる.
主な方法:
- プラチナの種を直接特徴づけ,定量化するために赤外線スペクトロスコーピーを利用する.
- 低温の触媒反応 (CO酸化,水-ガスシフト) を実行して活性性を評価する.
主要な成果:
- 赤外線スペクトロスコピーは ナノ粒子からプラチナの単一原子を効果的に区別します
- 低温でCO酸化と水-ガスシフトの触媒的活性を示すのはプラチナナノ粒子だけでした.
- プラチナの単一の原子は,強いCO結合による可能性があるため,活動を示さなかった.
結論:
- プラチナナノ粒子は単一の原子ではなく,低温CO酸化と水-ガスシフトの活性部位です.
- 赤外線光譜はプラチナの単一原子とナノ粒子を特徴づけるための貴重なツールです.
- 強いCO結合は,プラチナ単一の原子の触媒的可能性を制限する.
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