形结构碳与铁原子对和作为超高性能催化剂共同化,以减少氧气
Xiudong Shi1, Zonghua Pu1,2, Bin Chi1
1The Key Laboratory of Fuel Cell Technology of Guangdong Province School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|November 10, 2023
概括
这项研究引入了一种新的Fe-Fe双原子对催化剂,用于N-化碳 (N-CC@Fe DA) 的高级氧降解反应 (ORR). 这种先进的催化剂显著提高了Zn/空气电池和质子交换膜燃料电池 (PEMFC) 的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 有效的氧降解反应 (ORR) 对能量转换装置至关重要.
- 开发原子级过渡金属合碳催化剂是高电催化活性的关键.
- 现有的催化剂往往在活动和稳定性方面面临限制.
研究的目的:
- 设计和合成一种新型的电催化剂,在N-doped形碳 (N-CC@Fe DA) 上使用Fe-Fe双原子对.
- 评估性Zn/空气电池和质子交换膜燃料电池 (PEMFCs) 中N-CC@Fe DA催化剂的电催化ORR活性.
- 在ORR过程中阐明Fe-Fe双原子对的结构-活性关系.
主要方法:
- 气体兴奋剂的方法使用热氧化伊米达酸框架-8 (ZIF-8) 作为碳前体.
- 环二二二聚合物被用作Fe-Fe原子对的前体.
- 包括X射线光电子光谱 (XPS) 和X射线吸收光谱 (XAS) 在内的表征技术.
- 密度函数理论 (DFT) 计算以了解催化机制.
主要成果:
- 该N-CC@Fe DA催化剂显示出超高的电催化ORR活性.
- 在 Zn/空气电池中达到 241 mW cm−2 的峰值功率密度,在 PEMFC 中达到 724 mW cm−2 的峰值功率密度,性能优于传统的 Pt/C 催化剂.
- XPS和XAS证实了Fe原子对与N原子协调的存在.
- DFT计算显示,Fe-Fe对结构促进了氧吸附,O−O键激活和OH−脱附.
结论:
- 与N原子协调的Fe-Fe双原子对对于ORR催化非常有效.
- 在能源转换应用中,N-CC@Fe DA催化剂为贵金属催化剂提供了一个有希望的替代品.
- 这项工作为设计具有特定原子结构的高性能化碳催化剂提供了新的策略.
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