高表面積のLaFeO3に支えられた熱安定性を改善したスマートPd触媒
Tzia Ming Onn1, Matteo Monai2, Sheng Dai3
1Department of Chemical and Biomolecular Engineering , University of Pennsylvania , 34th Street , Philadelphia , Pennsylvania 19104 , United States.
Journal of the American Chemical Society
|January 11, 2018
まとめ
この研究は,高温アプリケーションのための自己再生触媒を導入します. 研究者らは,新しいペロブスキートでコーティングされたサポートを使用して安定したメタン酸化を達成し,触媒再生の以前の制限を克服しました.
科学分野:
- 材料科学
- カタリシス
- ナノテクノロジー
背景:
- 支えられた金属触媒は,高温で粒子が粗なり,効率が低下します.
- 既存の自己再生型触媒の概念は,低い支持面面積と短い金属イオン拡散長さのために制限に直面しています.
研究 の 目的:
- 自己再生する触媒の可逆活性化と安定した触媒性能を証明する.
- 以前の高温用途のペロブスキート系触媒設計の限界を克服する.
主な方法:
- 原子層沈殿 (ALD) は,多孔性マグネシウムアルミニウム酸化物 (MgAl2O4) 基板にランタン鉄酸化物 (LaFeO3) の薄いコンフォームコーティングを作成するために使用されました.
- 準備された触媒は,安定性と性能を評価するために,酸化還元サイクルおよび高温処理を受けた.
- メタン (CH4) と一酸化炭素 (CO) への触媒活性が評価されました.
主要な成果:
- 高表面積のサポート上の薄い (1.5 nm未満) LaFeO3膜は,最大900 °Cの安定性を示した.
- メタン酸化の可逆活性化と安定した触媒性能は,リドックスサイクルで達成された.
- この新しいアプローチは,金属イオン拡散と従来のペロブスキットの表面積の限界を克服します.
結論:
- 高表面積の基板に薄いペロブスキートコーティングを基にした自己再生する触媒は,高温の用途に適しています.
- このアプローチは,金属粒子の粗化に対する有望な解決策であり,触媒の寿命と性能を高めます.
- ペロブスキート組成とサポート構造の最適化に関するさらなる研究は,高度な触媒材料につながる可能性があります.
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