Crystal growth, differential gas adsorption, high thermal stability, and reversible coordination of two new barium-organic frameworks, Ba(SBA)(DMF)4 and Ba2(BTEC)(H2O)

Abstract

Single crystals of two barium-organic framework materials, Ba(SBA)(DMF)4 (CAUMOF-15) and Ba2(BTEC)(H2O) (CAUMOF-16), have been grown through solvothermal reactions (H2SBA=4,4′-sulfonyldibenzoic acid and H4BTEC=1,2,4,5-benzenetetracarboxylic acid). The crystal structures of the reported frameworks have been determined by single-crystal X-ray diffraction. The materials have been fully characterized by powder X-ray diffraction (PXRD), elemental analyses, Infrared (IR) spectroscopy, and thermogravimetric analyses (TGA). CAUMOF-15 reveals a three-dimensional open-framework that comprises of an inorganic motif with one-dimensional chains and the SBA linkers. CAUMOF-16 shows another three-dimensional backbone consisting of layers of edge-shared BaO9 and BaO10 polyhedra, and BTEC pillars. Both of the 3D frameworks exhibit relatively high thermal stabilities. The PXRD and IR spectral data confirm that CAUMOF-15 and CAUMOF-16 reveal reversible coordinations of the respective solvent molecules, DMF and H2O. Gas adsorption properties towards nitrogen, hydrogen, and carbon dioxide have been also investigated.