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Ni/Fe (Oxy) 水酸化物の反応性Feサイトは,異常な酸素電解活動に起因する
Michaela Burke Stevens1, Christina D M Trang1, Lisa J Enman1
1Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.
Journal of the American Chemical Society
|August 10, 2017
まとめ
ニッケル-鉄酸化水酸化物触媒の鉄は,酸素進化反応 (OER) の活性を著しく高める. この強化は,鉄の局所的な欠陥によるもので,大量代用によるものではありません.これは,特定の構造的な取り決めの重要性を強調しています.
科学分野:
- 電気化学
- 材料科学
- カタリシス
背景:
- ニッケル-Feオキシヒドロキシド (Ni(Fe) OxHy) は,酸素進化反応 (OER) の非常に活性な触媒である.
- OERの性能を向上させるための鉄 (Fe) の正確な役割は,まだ完全に理解されていません.
- Feの機能を理解することは より効率的な電気触媒の設計に不可欠です
研究 の 目的:
- Ni (Fe) OxHy触媒における異なる鉄種の役割を解明する.
- 大量または局所的なFeが強化されたOER活動に寄与するかどうかを判断する.
- Feの組み込み,Ni電圧測定,および触媒性能との関係を明確にする.
主な方法:
- Ni ((Fe) OxHy材料の合成と特徴づけについて
- OER活動を評価するために,周期的な電圧測定を含む電気化学的測定.
- 大量と表面/欠陥に関連したFe種を区別するための分析.
主要な成果:
- 2種類のFe種が特定されました. すぐにはエッジ/欠陥に組み込まれたFeと,大量にFeを代用するNi.
- 迅速に組み込まれたFe種は,強化されたOER活動に直接責任があります.
- 大量Fe置換は観測されたニッケル電圧測定に影響するが,固有のOER強化には影響しない.
結論:
- Ni ((Fe) OxHyの例外的なOER活動は,大量に代入されたFeではなく,局所的な場所 (エッジ/欠陥) でのFeに起因する.
- 大量ニケチオンのボルトメトリック特性は,触媒の高性能を説明するだけではない.
- 局所的な原子構造と欠陥部位は,Ni ((Fe) OxHyにおける優れたOER触媒の重要な要因である.
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