Three metal organic frameworks constructed with 2,2′:6′2′′-terpyridine-4′-carboxylic acid: syntheses, structures and selective dye adsorption
摘要
Three metal organic frameworks [Cu3(tpyc)3(H2btc)(Hbtc)·5H2O]n (1) [Mn(tpyc)(H2O)2·ClO4]n (2) and [Mn(tpyc)(bdc)0.5(H2O)]n (3) have been synthesized by using 2,2′:6′2′′-terpyridine-4′-carboxylic acid (Htpyc) in the presence of different auxiliary ligands (H3btc = 1,3,5-benzenetricarboxylic acid, H2suc = succinic acid, H2bdc = 1,4-benzene dicarboxylic acid) under solvothermal conditions. They were analyzed by elemental analysis, FT-IR, X-ray single crystal diffraction, PXRD and TGA. The results show that MOF 1 displays a 1D chain structure, which is further assembled to a 3D architecture via multiple intermolecular hydrogen bonds. MOF 2 also presents a 1D chain structure and the adjacent chains are further connected by hydrogen bonds O1–H1B∙∙∙O2#1, finally forming a 2D layered structure. For MOF 3, its 3D framework structure is formed by hydrogen bond O5–H5A∙∙∙O2#1 and O5–H5B∙∙∙O3#2 interaction between adjacent 1D chains. Furthermore, dye adsorption studies indicate that MOF 3 can selectively adsorb organic dye Congo red.