エタノールの直接の12電子酸化は,Ternary Au (コア) -PtIr (シェル) のエレクトロカタリスト
Zhixiu Liang1, Liang Song1, Shiqing Deng2
1Chemistry Division , Brookhaven National Laboratory , Upton , New York 11973 , United States.
Journal of the American Chemical Society
|May 28, 2019
まとめ
新しい金・プラチナ・イリジウム (Au@PtIr) コア・シェル触媒は,C−C結合の分裂を促進することによって,エタノール酸化反応 (EOR) の活性を劇的に高めます. この設計は12電子の完全な酸化経路を促進し,効率的な電気触媒のためにCO中毒を回避します.
科学分野:
- 材料科学
- 電気化学
- カタリシス
背景:
- 電気触媒反応の最適化には 合理的な触媒設計が不可欠です
- 基本的なステップにおける金属と原子構造の役割を理解することは,触媒の開発に役立ちます.
- エタノール酸化反応 (EOR) は,アルカリ燃料電池における重要なプロセスである.
研究 の 目的:
- 強化されたEORのための新しい三元 Au@PtIrコアシェル触媒を開発する.
- 触媒メカニズムを支配する構造-活動関係を明らかにする.
- 完全なエタノールの酸化を促進し,中介毒を最小限に抑える経路を調査する.
主な方法:
- Au@PtIrコアシェルの三元触媒の合成
- アルカリ溶液中のEORの電気触媒性能評価
- 触媒のインサイト赤外線反射吸収スペクトロスコーピー (IRRAS) 分析
- バイメタリックサブセット (Au@Pt,PtIr合金) と合金触媒との比較
主要な成果:
- Au@PtIr触媒は,AuPtIr合金よりも6度程度の活性強化を示しています.
- モナトミックステップとPtIrに対するAu誘発の張力により,C−C結合の分裂が容易になる.
- IRは低電位で脱水化を促進し,12電子の直接的酸化を可能にします.
- 低発生電位 (0.3V) と高ピーク電流 (8.3A mg-1all-metals) が達成されました.
結論:
- AuコアとPtIrシェルのシネジスティック効果は,EORの性能の向上の鍵です.
- 初期段階でのC−C結合分裂は,直接的な完全な酸化経路を活性化し,CO中毒を回避する.
- Au@PtIrコアシェル触媒は,効率的なエタノール電酸化のための重要な進歩を表しています.
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