Ozonolysis–oxidation-driven top-down strategy for the target preparation of ultrathin 2D metal–organic framework monolayers

摘要: Two-dimensional metal–organic-framework (2D MOF) nanosheets with a modular nature and tunable structures exhibit a bright future for sensors, separation, and catalysis. Developing ultrathin 2D MOF nanosheets with unique physical and chemical properties is urgently required but very challenging. Although the chemical exfoliation strategy has been regarded as a promising way to exfoliate large amounts of three-dimensional (3D) pillar-layered MOFs, this method still faces many problems and remains insufficient. In this study, a novel chemical exfoliation method is developed for the target preparation of 2D MOF monolayers from the 3D pillar-layered MOFs. The Co/Zn/Cu-MOFs with a pillar ligand of trans-1,2-bis(4-pyridyl)ethylene (bipyen) are subjected to be broken by the cleavage of CC bonds in the bipyen ligands via an ozone oxidation reaction. As chemical exfoliation is processed via the oxidation of the …