Two CuxIy-based copper–organic frameworks with multiple secondary building units (SBUs): structure, gas adsorption and impressive ability of I2 sorption and release

Two CuxIy-based copper–organic frameworks with multiple secondary building units (SBUs), [(Cu4I4)8(Cu8I6)(Dabco)8Cu12L24DMF12]·2NO3−·17DMF (1) and [(Cu4I4)CuL2(Dabco)1.5]·10H2O·2DMF (2) (Dabco = 1,4-diazabicyclo[2.2.2]octane, H2L = 4-pyridylbenzoate, DMF = N,N-dimethylformamide), have been successfully synthesized under solvothermal conditions and structurally characterized. Compound 1 possesses a 24-connected twisty truncated cuboctahedra supermolecular building block (SBB) constructed from a rare Cu8I6 cluster and 8 tetrahedral Cu4I4 SBUs, which is the first reported SBB based on CuxIy clusters. Compound 2 is a doubly interpenetrated MOF based on Cu4I4 and Cu-paddlewheel SBUs with a (4,6)-connected network. It is worth noting that the BET surface area of compound 2 ranks highly among the CuxIy-based MOF materials. In addition, both compounds exhibit high performance for I2 sorption and release.