调整单原子催化剂的协调环境,以实现高效的氧降低反应
Jinqiang Zhang1, Yufei Zhao1, Chen Chen2
1Center for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science , University of Technology Sydney , Ultimo , New South Wales 2007 , Australia.
Journal of the American Chemical Society
|December 6, 2019
概括
我们在N,S编码的碳中开发了单金属原子催化剂,用于高效的氧降解反应. 与和相比,以铁为中心的催化剂 (Fe-SAs/NSC) 的性能和稳定性优于商业/碳.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 原子分散的金属催化剂对于通过氧降解反应 (ORR) 进行高效的能量转换至关重要.
- 开发高活性和稳定的ORR催化剂对于推进燃料电池技术至关重要.
研究的目的:
- 合成和研究在多孔的N,S-编码碳 (NSC) 上固定单个金属原子,用于ORR.
- 探索Fe,Co和Ni单原子催化剂 (SAC) 在NSC上的结构性能相关性.
- 了解金属配合物对催化活性的影响.
主要方法:
- 模板辅助合成N,S编码的碳基质.
- 在NSC矩阵上固定单个Fe,Co和Ni原子.
- 使用先进的分析技术进行结构性表征.
- 电化学评估ORR活动和稳定性
- 密度函数理论 (DFT) 计算以阐明反应机制.
主要成果:
- 观察到不同的协调环境:Fe-SAs/NSC具有FeN4S2位,而Co-SAs/NSC和Ni-SAs/NSC则表现出M-S键形成MN3S1位.
- DFT计算预测FeN4S2的活性较高,这是由于其有利的电子特性和较低的能量障碍.
- Fe-SAs/NSC表现出优异的ORR性能,超过商业Pt/C,具有出色的甲醇耐受性和长期稳定性 (5000周期).
结论:
- 单个金属原子的协调结构显著影响ORR的催化活性.
- Fe-SAs/NSC是一种高效和稳定的ORR催化剂,为基催化剂提供了有前途的替代品.
- 这项研究为合理设计具有可调节性能的单原子催化剂提供了关键的见解.
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