強く結合されたコバルト酸化物ナノ結晶と炭素ナノチューブに基づく酸素還元電気触媒
Yongye Liang1, Hailiang Wang, Peng Diao
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|September 11, 2012
まとめ
新しいコバルト酸化物/炭素ナノチューブハイブリッド触媒は,酸素還元反応 (ORR) の高効率を提供します. この耐久性があり,低コストの触媒は,再生可能エネルギーと塩素-アルカリ電解の有望性を示しています.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 酸素還元反応 (ORR) は,再生可能エネルギー技術にとって不可欠です.
- 費用対効果が高く,高度に活性化され,耐久性の高いORR触媒の開発は,依然として大きな課題です.
- 既存の触媒は,しばしば性能と安定性の制限に直面しています.
研究 の 目的:
- 効率的なORR触媒として新しいコバルト酸化物/炭素ナノチューブ (CNT) ハイブリッドを合成する.
- 合成材料の触媒活性と耐久性を調査する.
- 塩素-アルカリ電解のための酸素分散型カソードにおけるその潜在的な応用を探求する.
主な方法:
- コバルト酸化物のナノ結晶が酸化された多壁のCNTに直接成長する2段階の合成です.
- NH(3) のガスフェーズアニリングにより,コバルト酸化物 (CoO) が形成されます.
- CoO/窒素ドーピングされたCNT (NCNT) ハイブリッドのORR性能と安定性の特徴.
主要な成果:
- CoO/NCNTハイブリッドは,高いORR電流密度を示し,Co(3) O(4) /グラフェンと商用Pt/Cを上回った.
- 触媒は主に4電子の還元経路を使用した.
- 金属酸化物/ナノチューブ・ハイブリッドは,グラフェン製の同種と比較して優れた活性部位と電荷輸送を示した.
- CoO/NCNTハイブリッドは,80°Cの10M NaOHで優れた活性と安定性を示した.
結論:
- 強く結合された無機/ナノカーボンハイブリッドは,ORR触媒の有望な新しいクラスを表しています.
- CoO/NCNTハイブリッドは,ORRアプリケーションの費用対効果が高く,耐久性の高い代替案を提供します.
- この触媒システムは,塩素-アルカリ電解のための酸素分散型カソッドで使用される可能性があります.
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