酸性環境における酸素還元のための高い活性を持つフェニレンダイアミンベースのFeN(x) / C触媒とその活性部位探査装置
Qiang Wang1, Zhi-You Zhou, Yu-Jiao Lai
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China.
Journal of the American Chemical Society
|July 18, 2014
まとめ
この研究では,酸素還元反応 (ORR) のための新しいポリ-m-フェニレンダイアミン鉄-窒素-炭素 (PmPDA-FeN(x) /C) 触媒を導入しています. 触媒は酸性条件下で高い活性と安定性を示し,鉄を明らかにします.
科学分野:
- 電気化学 電気化学について
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
背景:
- 鉄-窒素-炭素 (FeN(x) /C) 触媒は,酸素還元反応 (ORR) の非貴金属の代替品として有望である.
- 既存のFeN(x) / C触媒は,ORRの活動が不十分で,活性サイトがよく定義されていないため,しばしば課題に直面しています.
- 活性部位の構造を理解することは,酸性介質での触媒性能の最適化に不可欠です.
研究 の 目的:
- 新しいFeN(x) / C触媒を開発し,ORRの活性と酸性環境での安定性を向上させる.
- FeN(x) /C触媒における活性部位の性質を明らかにする.
- 一般的なORR毒に対する触媒の耐性,および中介物質との相互作用を調査する.
主な方法:
- ポリ-m-フェニレンダイアミン (PmPDA) を前体として使用したFeN(x) / C触媒の合成.
- 酸素還元反応 (ORR) の活性とH2O2の産出のための触媒の電気化学的特徴付け.
- CO,NOx,ハリドイオン,および硫黄を含む物体の存在における触媒性能の評価.
主要な成果:
- 合成されたポリ-m-フェニレンダイアミン鉄-窒素-炭素 (PmPDA-FeN(x) /C) 触媒は,高ORR活性 (0.80V対RHEで11.5A g(-1) と低H2O2収量 (<1%) を酸性で示した.
- 触媒は,H2O2.2の還元と酸化の両方において優れた活性を示した.
- ORRの活動は,COとNOxに対して無感であったが,ハリドイオンと低価硫黄種によって著しく抑制され,Fe種 (主にFe(III)) が活性部位に関与していることを示した.
結論:
- PmPDA-FeN(x) /C触媒は,酸性アプリケーションのための非貴金属ORR電触媒の重要な進歩を表しています.
- この研究は,ORR.のFeN (x) /C構造の中で,鉄の種,特にFe (III) の決定的な役割を確認しています.
- この発見は,活性部位構造と中毒メカニズムに関する貴重な洞察を提供し,将来の触媒設計の指針となっています.
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