三金属合金触媒の原子調整構造と強化された電解活性との相関関係
Bridgid N Wanjala1, Bin Fang, Jin Luo
1Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, United States.
Journal of the American Chemical Society
|June 30, 2011
まとめ
ナノエンジニアリングによるPtNiFe/C触媒は,酸素還元反応の温度依存の電気触媒性能を示しています. 高温は,プラチナの表面濃度が低下したにもかかわらず,改良された合金による特異的活性を増強します.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- カタリシス カタリシス カタリシス
背景:
- 燃料電池は,酸素還元などの反応のために,効率的な電気触媒に依存しています.
- 原子規模の構造-活性関係を理解することは,高度な触媒の設計に不可欠です.
研究 の 目的:
- 様々な温度で処理されたPtNiFe/C触媒の原子構造と電気触媒性能の相関を調査する.
- 燃料電池反応に影響を与える合金と相互作用構造に関する基本的な洞察を提供すること.
主な方法:
- 活動測定のための回転ディスク電極 (RDE) と陽子交換膜燃料電池 (PEMFC) 試験.
- 伝送電子顕微鏡 (TEM),X線 difraktion (XRD),X線光電子スペクトロスコーピー (XPS),X線吸収微細構造 (XAFS) 分析による構造的特徴づけを行う.
主要な成果:
- 温度上昇に伴い,質量活動が低下し,特定の活動が増加した.
- XAFSは,高温でヘテロ原子の調整と合金性が強化されたことを明らかにしました.
- XPSは,高温で表面Pt濃度の低下を示し,表面濃縮と合金との間のトレードオフを示した.
結論:
- 低温でのより高い質量活動は,Pt表面濃縮に起因する.
- 高温での高特異活性度は,強化されたPt合金表面部位によるものです.
- 発見は,原子規模の合金と格子構造を制御することによって,高度活性合金電触媒の設計に関する新しい洞察を提供します.
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