传统与非传统的氧降解反应中间体在单原子催化剂上
Tahereh Jangjooye Shaldehi1, Soosan Rowshanzamir1, Kai S Exner2,3,4
1Hydrogen & Fuel Cell Research Laboratory, School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, Tehran 16846-13114, Iran.
ACS applied materials & interfaces
|January 15, 2025
概括
这项研究探讨了氧降解反应 (ORR) 机制,使用化石墨烯的单原子催化剂. 它揭示了非常规的中间体可以更稳定,影响电催化活性和过量的潜力.
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
- 计算化学计算化学
背景情况:
- 氧降解反应 (ORR) 对燃料电池和金属空气电池等能源技术至关重要.
- 了解ORR机制是设计高效电催化剂的关键.
- 在配合石墨烯 (NG) 上的单原子催化剂 (SAC) 为ORR提供可调节的电子特性.
研究的目的:
- 通过使用DFT对M@NG (M = Sc-Zn, Pt) 进行传统和非传统ORR机制的研究.
- 确定稳定的反应中间体及其对电催化活性的影响.
- 确定有前途的SAC,以实现高效的ORR.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 对O2中间体的各种吸附几何学的分析.
- 热力学超电位和限制电位计算.
主要成果:
- 非传统的O2中间体 (超氧复合物) 通常比传统的更稳定.
- M@NG系统主要遵循非常规的路径,除了Cr@NG和Cu@NG,两者都在竞争.
- 传统的机制比非传统的产生更低的超潜力.
- 过渡金属具有较少的d电子显示较低的活动,由于更高的超电位.
结论:
- 对配合石墨烯 (Co@NG) 的是一种有前途的SAC,有利于低超电位 (0.38V) 和限制电位 (0.85V) 的常规机制.
- 在配合石墨烯 (Cu@NG) 上的铜是第二个最佳候选者.
- 催化剂设计应考虑传统和非传统的ORR路径,以获得最佳性能.
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