缺乏硫的边缘作为MoS2上的进化的活跃地点
Sander Ø Hanslin1,2, Hannes Jónsson2, Jaakko Akola1,3
1Department of Physics, Norwegian University of Science and Technology, No-7491, Trondheim, Norway. jaakko.akola@ntnu.no.
Physical chemistry chemical physics : PCCP
|November 24, 2023
概括
该研究显示,缺乏硫的二硫化 (MoS) 边缘,特别是那些富含原子的边缘,显著提高了演化反应 (HER) 动力学. 催化剂设计应优先考虑暴露这些活性金属位点,以有效生产气.
科学领域:
- 计算材料科学 计算材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 进化反应 (HER) 对于可持续的生产至关重要.
- 二硫化物 (MoS) 是 HER 的有前途的催化剂,但其内在活性因部位类型而异.
- 了解不同MoS2位点的电压依赖动力学和激活能量对于催化剂优化至关重要.
研究的目的:
- 在内在的MoS2位点上计算HER的电压依赖激活能量.
- 为了估计MoS2边缘上的HER动力学,具有不同的硫覆盖率和基底平面S空缺.
- 为了将理论上的超潜与实验发现相关联,并指导催化剂设计.
主要方法:
- 采用大法典的方法来计算激活能量和反应动力学.
- 在MoS2边缘 (不同的S覆盖) 和基底平面S空隙上研究了HER.
- 利用基于电压依赖反应能量学的动力学建模.
主要成果:
- 缺少S的Mo终结边缘表现出明显更高的HER活性,激活能量在0V与SHE相比低于0.5 eV.
- 富含Mo的地点对于高效的HER至关重要;富含S的地点显示出高能量障碍 (>1.5 eV).
- 理论上的超潜值与实验值保持一致,随着硫缺乏增加和Mo-协调减少而下降.
结论:
- MoS2催化剂的设计应侧重于暴露和修改用于增强 HER.的位.
- 缺乏硫和降低协调是降低过量的关键因素.
- 这项研究提供了关于Mo-rich与S-rich在过渡金属二二基因化物中的不同性能的基本见解.
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