强大的电子金属支相互作用使Co-N4活性位点的旋转状态增加,并提高了酸氧减氧反应的性能
Miao-Ying Chen, Shuhu Yin1, Gen Li2
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P.R. China.
使用单个原子和超低-纳米粒子的混合催化剂可提高酸性燃料电池中的氧降解反应 (ORR) 性能,显示出高效率和耐用性.
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:
- 非贵金属催化剂,特别是金属--碳 (M-N-C) 类型,是氧降解反应 (ORR) 的关键.
- 在酸性环境中,M-N-C催化剂和基催化剂之间存在显著的性能差距.
研究的目的:
- 开发混合催化剂,将单个原子和Pt3Co金属间纳米粒子 (NP) 结合起来,以提高ORR.
- 为了解决在酸性条件下M-N-C催化剂的性能限制.
主要方法:
- 合成具有单个Co原子和Pt3CoNP超低度的混合催化剂.
- 对ORR效率,耐久性和燃料电池性能进行催化剂的电化学测试.
- 理论计算以阐明增强ORR活动的机制.
主要成果:
- 在酸性条件下,混合催化剂实现了0.895V的ORR半波潜力.
- 经过8万个周期后,表现出异常稳定性,衰变微不足道.
- 在燃料电池中达到1.34W cm-2的高最大功率密度,超过现有的Co-N-C和Pt/Co-N-C催化剂.
结论:
- 增强的ORR活性归因于由Pt3Co NP诱导的Co位点的旋转密度增加.
- 这促进了O-O键的激活,并将反应途径转向离散过程.
- 这些发现为设计用于酸性燃料电池的先进M-N-C阴极提供了策略.
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