原子的に分散したPt1-ポリオキシメタラート触媒:金属支柱の相互作用が安定性と水素化活動にどのように影響するのですか?
Bin Zhang1, Geng Sun2, Shipeng Ding1
1Department of Chemical and Biomolecular Engineering , National University of Singapore , 4 Engineering Drive 4 , 117585 Singapore.
Journal of the American Chemical Society
|April 30, 2019
まとめ
ポリオキソメタレートにプラチナ原子を搭載した単原子触媒 (SAC) は高い安定性と活性を示している. これらのプラチナ SAC は,触媒力を損なうことなく,水素化反応の性能を改善します.
科学分野:
- 異質な触媒
- 材料科学
- 表面化学
背景:
- サポートされた単原子触媒 (SAC) は,原子的に分散した金属原子を特徴とし,重要な金属サポート相互作用につながります.
- これらの相互作用の安定性と触媒の影響を理解することは,高度な触媒の設計に不可欠です.
研究 の 目的:
- ポリオキソメタラート基体のプラチナ (Pt) 原子の安定性を定量的に調査する.
- 水素化反応におけるPt-サポート相互作用が触媒性能にどのように影響するか解明する.
主な方法:
- ポリオキソメタラート支持のPt触媒の合成と特徴付け
- 水素化反応における触媒性能の実験評価
- 反応経路とエネルギー学をシミュレートするための密度関数理論 (DFT) の計算.
主要な成果:
- Pt原子はポリオキシメタレットの4倍空洞部位で好ましく吸収され,最小吸収エネルギーは5.50 eVで,シンタリング抵抗を保証します.
- 水素化反応における触媒活動は,異なるPt-サポート相互作用において,類似した経路と低い有効バリア (24 kJ/mol) を示している.
- DFTは,反応はPt原子のみで,分子的に吸収されたH2経由で水素化が行われ,SACではより弱いH2吸収が行われていることを確認した.
結論:
- ポリオキソメタラートで高度に安定したプラチナSACを達成することは,触媒活性を犠牲にすることなく可能である.
- 観察された低活性化バリアは,クラスターまたは表面と比較してPt SACのより弱いH2吸収に起因する.
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