Sorption Properties and Nitroaromatic Explosives Sensing Based on Two Isostructural Metal-Organic Frameworks

We first designed and synthesized a new semirigid tripodal ligand with tetrazole groups, 1,3,5-tri(4-(2H-tetrazol-5-yl)phenoxy)benzene (H3TTPB). Two isostructural microporous metalorganic frameworks (MOFs), namely [Cu-3(TTPB)(2)(H2O)(6)]center dot 5DMF (JUC-130) and [Cd-3(TTPB)(2)(H2O)(6)]center dot 6DMF (JUC-131) (JUC = Jilin University, China), were successfully synthesized under solvothermal reactions based on this ligand, which both possess two-dimensional (2D) frameworks based on similar trinuclear metal centers as secondary building units (SBUs). H3TTPB was designed as the organic building block, not only because it is suitable to construct functionalized microporous frameworks with numerous nitrogen atoms but also by reason for its blue luminescent emission. Gas sorption measurements indicated that they are both microporous frameworks. JUC-130 showed high stability in water and selective sorption capabilities for alcohol and water vapors, which may be further used for the separation of alcohol-water mixtures. In addition, JUC-131 exhibited interesting and important fluorescent properties, which can be used as one of the few known MOFs useful for the detection of nitroaromatics via supramolecular wire effect.