Li Penghui, Wang Fang, Wei Shiqian, Li Xinyu, Zhou Ying
The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China.
The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China and State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China.
Phys Chem Chem Phys. 2017 Feb 8;19(6):4405-4410. doi: 10.1039/c6cp08409e.
In this study, DFT-D calculations were performed to explore the role of Cu and Mo loading in the CO conversion mechanism on a two-dimensional g-CN(001) surface. The introduced transition metals, Cu and Mo, significantly changed the electron distribution and band structures of g-CN. Moreover, two possible mechanisms for the reduction of CO to CO have been discussed in detail. We found that the energy barriers of the two mechanisms were largely reduced by Cu and Mo loading, and the dominant reaction path changed on different transition metal-loaded surfaces. Cu/g-CN(001) prefers to directly dissociate CO into CO, whereas cis-COOH is the preferred product of CO reduction on Mo/g-CN(001). Considering the activation barrier and reaction route selectivity, Mo-doped g-CN(001) was identified as a promising candidate for CO conversion. It is concluded that suitable transition metal doping can efficiently reduce the energy barrier and control route selectivity along the reaction paths over the g-CN surface. These findings could provide a helpful understanding of the CO reduction mechanisms and aid in the molecular design of novel g-CN catalysts for CO conversion.
在本研究中，进行了密度泛函理论（DFT-D）计算，以探究铜（Cu）和钼（Mo）负载在二维石墨相氮化碳（g-CN(001)）表面一氧化碳（CO）转化机制中的作用。引入的过渡金属铜和钼显著改变了g-CN的电子分布和能带结构。此外，还详细讨论了将CO还原为CO₂的两种可能机制。我们发现，通过负载铜和钼，这两种机制的能垒大幅降低，并且在不同过渡金属负载的表面上，主导反应路径发生了变化。Cu/g-CN(001)更倾向于将CO直接解离为CO，而顺式羧基（cis-COOH）是Mo/g-CN(001)上CO还原的首选产物。考虑到活化能垒和反应路径选择性，钼掺杂的g-CN(001)被认为是一种有前景的CO转化候选材料。研究得出结论，合适的过渡金属掺杂可以有效降低能垒，并控制g-CN表面反应路径的选择性。这些发现有助于理解CO还原机制，并有助于设计用于CO转化的新型g-CN催化剂的分子设计。
