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基于乙胺的FeN(x) /C催化剂具有高活性,用于在酸性介质中减少氧气,其活性位点探测
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
概括
这项研究引入了一种新的聚-m-phenylenediamine铁--碳 (PmPDA-FeN(x) /C) 催化剂,用于氧减少反应 (ORR). 催化剂在酸性条件下表现出高活性和稳定性,揭示出铁.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 铁--碳 (FeN(x) /C) 催化剂是氧降解反应 (ORR) 的非贵金属替代品.
- 现有的FeN(x) /C催化剂经常面临ORR活动不足和定义不良的活性位点的挑战.
- 了解活性部位结构对于优化酸性介质中的催化剂性能至关重要.
研究的目的:
- 开发一种具有增强ORR活性和在酸性环境中稳定的新型FeN(x) /C催化剂.
- 为了阐明FeN(x) /C催化剂中的活性位点的性质.
- 研究催化剂对常见ORR毒素的耐受性及其与中间体的相互作用.
主要方法:
- 合成FeN(x) /C催化剂,使用聚二胺 (PmPDA) 作为前体.
- 氧降解反应 (ORR) 活性和H2O2产量的催化剂的电化学表征.
- 在存在CO,NOx,化物离子和含硫物种的情况下评估催化剂性能.
主要成果:
- 合成的聚乙胺铁碳 (PmPDA-FeN(x) /C) 催化剂在酸中表现出高ORR活性 (11.5 A g(-1) 在0.80V与RHE) 和低H2O2产量 (<1%).
- 催化剂在减少和氧化H2O2.2方面表现出极好的活性.
- ORR活动对CO和NOx不敏感,但被化物离子和低价值硫物种显著抑制,表明Fe物种 (主要是Fe(III)) 在活性位点的参与.
结论:
- PmPDA-FeN(x) /C催化剂代表了非贵金属ORR电催化剂在酸性应用中的重大进步.
- 这项研究证实了铁物种,特别是Fe (III) 在ORR的FeN (x) /C结构中的关键作用.
- 这些发现提供了对活性部位结构和中毒机制的宝贵见解,指导了未来的催化剂设计.
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