A Porous Metal-Organic Framework Based on Triazoledicarboxylate Ligands - Synthesis, Structure, and Gas-Sorption Studies

A new porous metal-organic framework (MOF) {[CuL]center dot DMF center dot 2H2O}n [1a, H2L = 5-(4H-1,2,4-triazol-4-yl)benzene-1,3-dicarboxylic acid; DMF = N,N-dimethylformamide] with zigzag-shaped, narrow channels was prepared by solvothermal synthesis and structurally characterized. 1a has zigzag-shaped, open channels with micropore sizes of approximately 5.6 x 4.6 angstrom 2. The (3,6)-connected network of 1a leads to an a-PbO2 (apo) topology. The adsorption properties (N2, H2, and CO2) of the desolvated sample 1c have been studied. The results show that 1c has a highly porous structure and a high adsorption capacity: the total capture of CO2 at 1 bar and 298 K is 22.01 wt.-%, and the total H2 uptake at 1 bar and 77 K is 1.46 wt.-%. This high adsorption capacity can be attributed to strong interactions between the small gas molecules and the irregularly open channels with their zigzag shape and their narrow pore size.