1
|
Liu H, Liu W, Xue G, Tan T, Yang C, An P, Chen W, Zhao W, Fan T, Cui C, Tang Z, Li G. Modulating Charges of Dual Sites in Multivariate Metal-Organic Frameworks for Boosting Selective Aerobic Epoxidation of Alkenes. J Am Chem Soc 2023; 145:11085-11096. [PMID: 37162302 DOI: 10.1021/jacs.3c00460] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Selective aerobic epoxidation of alkenes without any additives is of great industrial importance but still challenging because the competitive side reactions including C═C bond cleavage and isomerization are difficult to avoid. Here, we show fabricating Cu(I) single sites in pristine multivariate metal-organic frameworks (known as CuCo-MOF-74) via partial reduction of Cu(II) to Cu(I) ions during solvothermal reaction. Impressively, CuCo-MOF-74 is characteristic with single Cu(I), Cu(II), and Co(II) sites, and they exhibit the substantially enhanced selectivity of styrene oxide up to 87.6% using air as an oxidant at almost complete conversion of styrene, ∼25.8% selectivity increased over Co-MOF-74, as well as good catalytic stability. Contrast experiments and theoretical calculation indicate that Cu(I) sites contribute to the substantially enhanced selectivity of epoxides catalyzed by Co(II) sites. The adsorption of two O2 molecules on dual Co(II) and Cu(I) sites is favorable, and the projected density of state of the Co-3d orbital is closer to the Fermi level by modulating with Cu(I) sites for promoting the activation of O2 compared with dual-site Cu(II) and Co(II) and Co(II) and Co(II), thus contributing to the epoxidation of the C═C bond. When other kinds of alkenes are used as substrates, the excellent selectivity of various epoxides is also achieved over CuCo-MOF-74. We also prove the universality of fabricating Cu(I) sites in other MOF-74 with various divalent metal nodes.
Collapse
Affiliation(s)
- Hanlin Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wei Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guangxin Xue
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
| | - Ting Tan
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Caoyu Yang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Pengfei An
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wenxing Chen
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100181, P. R. China
| | - Wenshi Zhao
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Ting Fan
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
| | - Chengqian Cui
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zhiyong Tang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guodong Li
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|