Synthesis, Characterization And Structure Determination Of Porous Metal-phosphonates

Organic-inorganic hybrid materials are novel porous materials. They have lots ofpotential utilizations in the field of catalysis, separation, sorption, host-guestchemistry and functional materials. Therefore, the materials have drawn muchattention in recently years.The thesis focused on the two main subjects. Firstly, three novelmetal-methylphosphonates were synthesized by using template-assisted method;secondly, two novel hexagonal tubular metal 1-hydroxyethylidenediphosphonateswere synthesized by utilizing hydrothermal technology. The synthesized materialswere characterized by EDX, GC-MS, EPMA, FTIR, NMR, TG, DTA, XRD, nitrogenadsorption-desorption measurements and X-ray single-crystal diffraction. Someinteresting results were obtained.DBMP (dibutyl methylphosphonate) could be used as template for synthesizingporous methylphosphonates. The incorporated template could be removed efficientlyfrom the as-synthesized precursor by evaporation in vacuum or by hydrothermaltreatment without destroying the hybrid structures. The post-synthesis treatment hasgreat effects on the structures of the products.Two novel hexagonal tubular metal 1-hydroxyethylidenediphosphonates,DLES-Alt and DLES-CrAl, were synthesized by using hydrothermal technology.Their structures were determined by single-crystal X-ray diffraction. They areisostructural with layered crystal structures, propeller-like chiral motifs, andhexagonal rings along [001]. Moreover, there is a chiral quaternary carbon in the1-hydroxyethylidenediphosphonic (hedp) ligand. Several new crystals with differentmorphologies have been synthesized in different reaction conditions. The newcrystals are designated as DLES-Alt,DLES-Alp,DLES-Als and DLES-Alts,respectively. The order of cell dimension is DLES-Als > DLES-Alts > DLES-Alt >DLES-Alp. Furthermore, another two novel crystals of chrominium1-hydroxyethylidenediphosphonate (DLES-Cr) and NH3CH2CH2NH3) Na2(hedp)·4H2O (SDP-2) were synthesized successfully. In the above seven new crystals,hedp shows four novel coordination modes.