解开对异核单原子催化剂氧降低活动的特定物种负荷影响
Tong Yang1, Keda Ding1, Jun Zhou2
1Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China.
Small methods
|November 18, 2024
概括
负载效应显著影响异核单原子催化剂 (SAC). Fe位点显示活性下降,而Co位点在特定负载下表现为氧减少反应 (ORR) 的最佳性能.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 计算化学的计算化学
背景情况:
- 高密度单原子催化剂 (SAC) 对于先进的应用至关重要.
- 了解异核SAC中的负载效应至关重要,但仍然有限.
- 邻近的SAC之间的相互作用会影响催化性能.
研究的目的:
- 为了研究负载对异质核SAC的特定地点活动的影响.
- 模拟Fe和Co SACs在基合石墨烯上进行氧降解反应 (ORR).
- 阐明Fe和Co网站的不同负载依赖行为.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 模拟的重点是Fe和Co单原子催化剂 (SAC) 在添加剂的石墨烯上.
- 分析包括特定站点的活动,站点间距离和电子结构.
主要成果:
- 铁站点在增加负载时显示活动的振荡性下降.
- 这些地点表现出类似火山活动,峰值约为16.8%的重量负荷 (7年间地点距离).
- 在超高负荷 (38.4 wt.%,4 Å) 时,只有Co位点对ORR保持活跃,而Fe位点变得不活跃.
结论:
- 负载效应显著影响异核SAC的催化活性.
- 基质结合和d轨道占用的差异解释了不同的Fe和Co位点行为.
- 这些发现对于设计高性能异质核和高的SAC在高负载状态中至关重要.
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