A porous layered metal-organic framework from π–π-stacking of layers based on a Co6 building unit

The coordination of benzene-1,3,5-tribenzoate (BTB) and imidazole (Im) with cobalt under basic conditions yields a 2D layered structure, Co3(BTB)1.5(Im)1.35(O)0.5(OH)0.5(H2O)1.65 guests (1), in which the imidazoles are weakly π–π stacked and hydrogen bonded to the adjacent layers affording a 3D supramolecular network. The structure is based on a hexanuclear Co6 building unit which comprises four octahedral and two tetrahedral Co(II) centres. The framework is permanently porous to N2, CO2 and CH4, with the strength of interaction at zero coverage being comparable to that at high loading.

Figure optionsDownload as PowerPoint slideHighlights
► This metal-organic framework contains a novel Co6 cluster.
► 2D layers are packed into a porous 3D arrangement through synergic π–π stacking interactions.
► The activation conditions of the framework govern the surface area of the material.
► The framework is porous to N2, CO2 and CH4.