作为氧降解反应的活性场所的碳缺陷中的原子合物种的协调
Longzhou Zhang1, Julia Melisande Theresa Agatha Fischer2, Yi Jia1
1School of Environment and Science and Queensland Micro- and Nanotechnology Centre , Griffith University , Nathan Campus, Nathan , Queensland 4111 , Australia.
Journal of the American Chemical Society
|August 8, 2018
概括
在碳 (A-CoPt-NC) 上原子分散的-催化剂具有优越的氧降解反应 (ORR) 活性和耐用性. 这一突破为广泛的ORR应用提供了传统催化剂的成本效益替代品.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- (Pt) 是氧降解反应 (ORR) 的主要催化剂,但由于成本和稀缺性而受到限制.
- 减少Pt的使用是克服其大规模应用的关键.
- 原子分散金属催化剂具有高活性和原子效率,可能满足这一需求.
研究的目的:
- 开发和描述一种新型的低Pt催化剂,以实现高效的ORR.
- 在碳支上研究原子Pt-Co的催化性能和机制.
- 展示一个可行的替代传统催化剂.
主要方法:
- 一个局部分布的原子Pt-Co碳基催化剂 (A-CoPt-NC) 的合成.
- 电化学测试以评估ORR活动和耐用性,包括质量活动比较.
- 密度功能理论 (DFT) 的计算以阐明催化机制.
主要成果:
- 与商业Pt/C相比,A-CoPt-NC催化剂的质量活性显著提高 (267倍),耐久性强.
- A-CoPt-NC选择性地支持ORR中的4e-路径,与原子Pt催化剂的2e-路径不同.
- DFT计算显示了原子Pt-Co和缺陷的C/N石墨烯表面 (N8V4空缺) 之间的协同作用,导致了高活性.
结论:
- 在-碳支器上的原子分散Pt-Co催化剂对ORR具有高度活性和耐用性.
- 增强的性能归因于N8V4空缺中的原子Pt-Co协调产生的协同效应和独特的电子特性.
- 这种催化剂设计为减少ORR应用中的含量提供了一个有希望的策略.
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