通过轴 Fe4 C 实现的 d-轨道电子移位 原子集群提供高性能 Fe-N-C 催化剂,用于氧降解反应
Long-Ji Yuan1, Bo Liu2, Li-Xiao Shen3
1Shenzhen Key Laboratory of Special Functional Materials, Shenzhen Engineering Laboratory for Advance Technology of Ceramics, Guangdong Research Center for Interfacial Engineering of Functional Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China.
Advanced materials (Deerfield Beach, Fla.)
|July 14, 2023
概括
一种新型的-Fe-N-C催化剂稳定了使用Fe4C集群的活性Fe-pyrrolic N4位点,用于燃料电池中高效的氧降解反应.
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 (Fe-N-C) 催化剂在质子交换膜燃料电池 (PEMFC) 中的氧降解反应 (ORR) 中是的有希望的替代品.
- 铁烯酸N4结构被确定为ORR高度活跃的部位,但其稳定性仍然是一个重大挑战.
- 开发稳定高效的非贵金属催化剂对于推进燃料电池技术至关重要.
研究的目的:
- 构建一个稳定的Fe-N-C催化剂与Fe-pyrrolic N4活性中心,以提高ORR性能.
- 调查轴 Fe4C 原子集群在稳定 Fe-pyrrolic N4 结构和优化催化活性中的作用.
- 通过原子集群相互作用来探索调整单原子催化剂电子结构的新策略.
主要方法:
- 合成一种含有Fe-pyrrolic N4活性中心和轴性Fe4C原子集群的-Fe-N-C催化剂.
- 在酸性环境中对催化剂的ORR活性进行电化学评估,包括半波电位测量.
- 在H2-O2和H2-Air燃料电池中测试催化剂的性能,以确定功率密度.
- 理论计算 (例如,DFT) 和现场光谱分析以分析电子结构和结合相互作用.
主要成果:
- 合成的Cyan-Fe-N-C催化剂在酸性介质中实现了0.836V (相对于RHE) 的ORR高半波潜力.
- 催化剂在1.0bar时提供了令人印象深刻的870mWcm-2 (H2-O2) 和478mWcm-2 (H2-Air) 的功率密度.
- 理论和光谱分析证实,轴性Fe4C集群通过扰乱其电子特性和优化OH*吸附来稳定Fe-pyrrolic N4结构.
结论:
- 轴性Fe4C原子集群有效地稳定了Fe-pyrrolic N4活性位点,克服了Fe-N-C催化剂开发中的一个主要挑战.
- 单个原子和原子集群之间的强烈相互作用为设计具有定制电子结构的先进单原子催化剂提供了可行的策略.
- 这项工作为为燃料电池应用开发高效和稳定的非贵金属催化剂铺平了道路.
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