Two New Metal−Organic Frameworks with Mixed Ligands of Carboxylate and Bipyridine: Synthesis, Crystal Structure, and Sensing for Methanol

Two new mixed ligand metal−organic frameworks, [Cu2(OH)(2,2′-bipy)2(BTC)·2H2O]n (1) and [Co(4,4′-bipy)(m-BDC)]n (2), have been synthesized by hydrothermal reaction of Cu(COO)2·H2O with 1,3,5-benzenetricarboxylic acid (H3BTC) and 2,2′-bipyridine and of Co(NO3)2·6H2O with 1,3-benzenedicarboxylic acid (m-H2BDC) and 4,4′-bipyridine, respectively. They were characterized by single-crystal X-ray diffraction analysis, powder XRD, elemental analysis, TGA, and IR spectroscopy. The adsorption characteristics of compounds 1 and 2 for methanol were investigated in situ with a quartz crystal microbalance (QCM), which indicated that they were highly sensitive to methanol at room temperature.