燃料化学学报（中英文）2025，Vol.53Issue(10)：1540-1552,13.DOI:10.1016/S1872-5813(25)60592-5
Ag、Zn掺杂Cu/MOR催化甲烷中C-H键活化的构效关系研究
Structure-activity relationships and catalytic performances of Ag-and Zn-doped Cu/MOR for methane C-H bond activation
摘要
Abstract
Efficient activation of the C-H bond in methane(CH4)is critical for achieving methane conversion at low-temperature.In this study,based on the theoretical screening by using the spin density(ρ)of active O atom as the activity descriptor,density functional theory(DFT)was employed to investigate the adsorption of CH4 and the mechanism of the following C-H bond activation on Ag-and Zn-doped[Cu3O3]2+/MOR surfaces,as well as Zn-doped[CuOCu]2+/MOR surfaces,which have a high ρ value indicating high catalytic activation.The results demonstrated that CH4 physisorbs on active O atom,which is further activated to give CH3·radical and surface OH groups via the radical reaction mechanism.Both Ag and Zn doping lower the activation energy and reaction energy for the cleavage of C-H bond in CH4,promoting the C-H activation.Further electronic structure analysis revealed the spin polarization of electronic orbitals for both the active O atom and their bonded metal atoms.After Ag doping on[Cu3O3]2+/MOR,the formation of an Ag-O bond increases the gap between the spin-up and spin-down p-band centers of O 2p(△εp)and its spin density(ρ),consequently enhancing the catalytic performance of the active O atom for the activation of C-H bond in CH4.Zn doping onto both[Cu3O3]2+/MOR and[CuOCu]2+/MOR also increases △εp.Especially,when the Zn 4ss and Zn 4p orbitals shift downward to appropriate lower energy levels,Zn 4s and Zn 4p can interact with O 2p,endowing active O atom with the half-metallic characteristic.This half-metallic characteristic exceptionally promotes the activation of the C-H bond in CH4,which is insufficiently predicted by the activity descriptors △εp and ρ.关键词
Cu/MOR/Zn掺杂/甲烷C-H键活化/半金属特征/密度泛函理论Key words
Cu/MOR/Zn doping/activation of C-H bond in CH4/half-metallic characteristic/density functional theory分类
化学化工引用本文复制引用
杨乐,吕学勇,刘子乐,阎智锋,左志军..Ag、Zn掺杂Cu/MOR催化甲烷中C-H键活化的构效关系研究[J].燃料化学学报（中英文）,2025,53(10):1540-1552,13.基金项目
The project was supported by the special fund for Science and Technology Innovation Teams of Shanxi Province(202204051001009),Fundamental Research Program of Shanxi Province(202303021221025,202403021222339)and Scientific and Technologial Innovation Programs of Higher Education Institutions in Shanxi(2024L343).山西省科技创新人才团队专项(202204051001009),山西省基础研究计划(202303021221025,202403021222339)和山西省高等学校科技创新项目(2024L343)资助 （202204051001009）
