Tuning Two-Dimensional Layer to Three-Dimensional Pillar-Layered Metal–Organic Frameworks: Polycatenation and Interpenetration Behaviors

A two-dimensional honeycomb network of {[Zn2(bpydb)2­(H2O)2]­(DMA)3­(H2O)}n (1) was solvothermally synthesized and structurally characterized. By employing 4,4′-bipyridine (bpy) as a pillar, two additional three-dimensional (3D) metal–organic frameworks (MOFs) of {[Zn2(bpydb)2­(bpy)­(EtO-H)2]­(DMF)­(EtOH)}n (2) and {[Zn­(bpydb)­(bpy)]­(DMA)­(EtOH)6}n (3) (bpydbH2 = 4,4′-(4,4′-bipyridine-2,6-diyl) dibenzoic acid, DMA = N,N- dimethylacetamide, DMF = N,N-dimethylformamide) were obtained. MOF 2 displays a 3D pillar-bilayered network generated from polycatenation of the 2D bilayers. By carefully adjusting the reaction condition, MOF 3 was harvested, showing a 2-fold interpenetrated (3,5)-connected hms net. The phase purity, thermal stability, and luminescent properties of the three MOFs were studied. In addition, N2 and CO2 adsorption behaviors of the activated 3 were investigated.