Mesoporous Hexanuclear Copper Cluster-Based Metal–Organic Framework with Highly Selective Adsorption of Gas and Organic Dye Molecules

Despite many advances
in the design and assembly of mesoporous
metal–organic frameworks (meso-MOFs), it is still a challenge
to obtain the desired structure. Here, we utilized an effective cluster
cooperative assembly strategy by introducing SO42– ions as chelating binding sites to construct a novel mesoporous
MOF, [Cu8(SO4)­(TBA)6(OH)2(N,N-dimethylacetamide (DMA))4]·12DMA·12CH3OH [JLU-MOF51, H2TBA = 4-(1H-tetrazol-5-yl)-benzoic acid]. Remarkably, the cooperative
assembly of the infrequent hexanuclear [Cu6SO4(OH)2] cluster and the classical paddlewheel [Cu2(CO2)4] via linear hetero-N, O donor ligand
results in an open three-dimensional framework, which possesses one-dimensional
nanometer tube channels with the diameter of 24 and 28 Å. Fascinatingly, JLU-MOF51 displays an exceptionally large Langmuir surface
area (5443 m2 g–1) and exhibits a high
capacity for selective adsorption of C3H8 (C3H8: 348 cm3 g–1 at
273 K; C3H8/CH4 = 220 at 298 K).
In addition, JLU-MOF51 can selectively adsorb fluorescein
disodium salt dye among numerous organic dyes. An extremely high surface
area and unique structural characteristics make JLU-MOF51 a promising meso-MOF material for the adsorption and separation
of hydrocarbon gases and organic dyes. Moreover, this strategy will
provide an effective means for constructing meso-MOFs via one-step
synthesis.