酸素還元反応のための複数のアクティブサイトを持つ超小型の高エントロピーインターメタリック
Tao Chen1, Chunyu Qiu2, Xinkai Zhang3
1Beijing Key Laboratory of Theory and Technology for Advanced Batteries Materials, School of Materials Science and Engineering, Peking University, Beijing 100871, P.R. China.
Journal of the American Chemical Society
|December 28, 2023
まとめ
研究者らは,超小型のプラチナ・鉄・コバルト・ニッケル・銅・亜鉛の高エントロピーインターメタリック (PFCNCZ-HEI) ナノ粒子を開発した. これらの触媒は,燃料電池の応用において,酸素還元反応の活性が著しく強化されていることを示している.
科学分野:
- 材料科学
- 電気化学
- ナノテクノロジー
背景:
- 原子レベルの多金属組を制御することは,特に5つ以上の元素を持つ高エントロピー合金 (HEAs) には大きな課題があります.
- 効率的な電気触媒の開発は燃料電池のようなクリーンエネルギー技術の発展に不可欠です.
研究 の 目的:
- 高エントロピー金属間 (HEI) ナノ粒子触媒を合成し,特徴づけること.
- 酸素還元反応 (ORR) の新しい触媒の電解性能を評価する.
- 陽子交換膜燃料電池 (PEMFC) の可能性を探求する.
主な方法:
- 超小型 (∼2 nm) PtFeCoNiCuZn高エントロピーインターメタリック (PFCNCZ-HEI) ナノ粒子を合成するための空間限定戦略を使用した.
- PFCNCZ-HEIのORR活動を電気化学測定で評価した.
- PFCNCZ-HEIをカタリストとして使って PEMFCを組み立て,その性能を評価した.
- 電子構造と活性サイトを理解するために理論的な計算を行いました.
主要な成果:
- 0. 90VでORRに対する超高質量活性2. 403 A mgPt-1を達成し,商用Pt/Cより19倍高い.
- 1.4W cm-2の電力密度と45W mgPt-1の質量標準化された定番電力を持つPEMFCを実証した.
- 理論的な計算では,高貴金属でない原子の外部の電子が調節され,複数のアクティブセンターが作られることが示されました.
結論:
- 開発されたPFCNCZ-HEIナノ粒子は,ORRにとって例外的な電解活性を示しています.
- 空間限定合成戦略は,高度にオーダーされたHEIナノ粒子を作るのに有効です.
- この研究は,電気触媒における高度に秩序付けられたHEIナノ粒子の有望な触媒設計を提供します.
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