Guo Zhichao, Chen Shuyue, Yang Bo
School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China.
iScience. 2023 Feb 18;26(3):106237. doi: 10.1016/j.isci.2023.106237. eCollection 2023 Mar 17.
Dry reforming of methane (DRM) is an efficient process to transform methane and carbon dioxide to syngas. Nickel could show good catalytic activity for DRM, whereas the deactivation of nickel surfaces by the formation of inert carbon structures is inevitable. In this study, we carry out a detailed investigation of the evolution and catalytic performance of the carbon-covered surface structure on Ni(100) with a combined density functional theory and microkinetic modeling approach. The results suggest that the pristine Ni(100) surface is prone to carbon deposition and accumulation under reaction conditions. Further studies show that over this carbon-covered reconstructed Ni(100) surface, a carbon-based Mars-van-Krevelen mechanism would be favored, and the activity and coke resistance is promoted. This surface state and reaction mechanism were rarely reported before and would provide more insights into the DRM process under real reaction conditions and would help design more stable Ni catalysts.
甲烷干重整（DRM）是一种将甲烷和二氧化碳转化为合成气的有效过程。镍对DRM可表现出良好的催化活性，然而，镍表面因形成惰性碳结构而失活是不可避免的。在本研究中，我们采用密度泛函理论和微观动力学建模相结合的方法，对Ni(100)上碳覆盖表面结构的演变及其催化性能进行了详细研究。结果表明，在反应条件下，原始的Ni(100)表面易于发生碳沉积和积累。进一步研究表明，在这种碳覆盖的重构Ni(100)表面上，基于碳的Mars-van-Krevelen机理更有利，且活性和抗积炭性能得到提升。这种表面状态和反应机理此前鲜有报道，将为实际反应条件下的DRM过程提供更多见解，并有助于设计更稳定的镍催化剂。
