表面原子の反応による移動による移行金属の活性部位の形成
Lang Xu1, Konstantinos G Papanikolaou1, Barbara A J Lechner2,3
1Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
Science (New York, N.Y.)
|April 6, 2023
まとめ
金属表面でのアドソルベート誘発のクラスター形成は,触媒の振る舞いを変化させる可能性があります. アダトムの形成エネルギーは,この現象の条件を予測し,触媒反応を理解するために不可欠です.
科学分野:
- 表面科学
- カタリシス
- コンピュータ化学
背景:
- 低指数単結晶表面は金属ナノ粒子触媒の一般的なモデルである.
- 実験データでは,これらの表面でアドソルベート誘発のサブナノメートルクラスター形成が示され,その妥当性が疑問視されています.
- クラスター形成を理解することは 触媒の正確な設計に不可欠です
研究 の 目的:
- 金属表面でのアドソルバート誘発のクラスター形成につながる条件を解明する.
- 原子形成エネルギーを用いてクラスター形成を好む条件をスクリーニングする方法を開発する.
- CO と NH3 の酸化のような触媒反応に対するこれらの発見の関連性を調査する.
主な方法:
- 原子形成エネルギーを決定するための密度関数理論 (DFT) の計算.
- クラスター形成のダイナミクスをモデル化するための運動モンテカルロ (KMC) シミュレーション
- 特定の金属表面でのクラスター形成を観察するためのスキャニングトンネル顕微鏡 (STM).
主要な成果:
- クラスター形成を促進する特定の金属表面中間組合せを特定した.
- アダトーム形成エネルギーは,アドソルベート誘発のクラスター形成の条件を効果的にスクリーン化します.
- 銅の表面でのCO誘発のクラスター形成とNi ((""1) の構造感受性が解明された.
- 金属結合破裂と触媒構造の進化は,これまで考えられていたよりも広範囲に広がっています.
結論:
- アドソルバート誘発のクラスター形成は,触媒の構造と性能に大きな影響を及ぼします.
- 原子形成エネルギーを用いたDFTベースのスクリーニングは,触媒の行動を予測するための強力なツールです.
- 触媒の設計は,反応条件下で動的構造の進化を考慮しなければならない.
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