興奮状態のN2 解離経路はFe-機能化されたAuで
John Mark P Martirez1, Emily A Carter1
1Department of Mechanical and Aerospace Engineering and ‡School of Engineering and Applied Science, Princeton University , Princeton, New Jersey 08544-5263, United States.
Journal of the American Chemical Society
|March 8, 2017
まとめ
局所化された表面プラズモン共鳴 (LSPR) は,光活性化触媒を可能にします. この研究では,LSPRは,アンモニア合成の重要なステップである窒素解離のエネルギーバリアを大幅に低下させることが示されています.
科学分野:
- 表面科学と触媒
- プラズモニクスとナノテクノロジー
- コンピュータ化学
背景:
- 局所的な表面プラズモン共鳴 (LSPR) は,金属ナノ粒子の光駆動化学反応を容易にする.
- 窒素 (N2) 解離は,ハーバー・ボッシュプロセスを通してアンモニア合成の挑戦的でエネルギー集約的なステップです.
- N2解離の高活性化エネルギーを克服することは,効率的なアンモニア生成に不可欠です.
研究 の 目的:
- 触媒表面でのN2解離の活性化エネルギーを低下させるLSPRの可能性を調査する.
- プラズモニック効果による強化されたN2解離のためのFe-ドーピングされたAu(111) 表面の使用を調査する.
- Fe−ドーピングされたAu−111表面でのN2解離のための興奮状態の潜在エネルギー表面を計算する.
主な方法:
- 密度関数埋め込み理論と埋め込まれたn-電子のバレンスの二次波動理論.
- N2解離のための興奮状態の潜在エネルギー表面の計算.
- Fe-ドーピングされたAu111) 表面でのN2解離のモデリング.
主要な成果:
- FeをドーピングしたAu111のN2の基底解離活性化エネルギーは,Feを活性部位として4.74 eV/N2であると計算された.
- 電子的に興奮した状態間の複数の共振エネルギー転送 (RET) が特定された.
- これらのRETは,解離バリアを1.33 eVに効果的に低下させました.
結論:
- LSPRは,共鳴エネルギー転送と組み合わせて,N2解離のための活性化バリアを大幅に低下させることができます.
- このプラズモン強化アプローチは,アンモニア合成の運動的制限を克服する有望な経路を提供します.
- この発見は 複雑な化学変化を容易にするために 光エネルギーを活用する戦略を示しています
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