Synthesis And Characterization Of Metal Phosphites With Open-framework

The prospects of designing and synthesizing the compounds with microporoussolids are of great interest for their potential applications in the fields of molecularsieves, ion-exchange, catalysis, and separations. As part of the renaissance in thestudy of open-framework metal phosphates, a series of novel compositions ofinorganic frameworks with one-, two- or three-dimensions (1-D, 2-D or 3-D) havebeen prepared by using polar organic molecules as structural directors. However,there have been great challenges and opportunities in terms of controlling their shapeand size for selective applications, because the crystallization process is manipulatedby various factors, such as solvent, gel composition, type of templates, crystallizationtime and temperature. For the structural feature of the pyramidal [HPO3 ] hydrogen 2-phosphite group, representing a member of the phosphorus oxoanions, can make atmost three links to adjacent cations via P-O-M (M = metal) bonds and provide morevariety and novelty of the new materials. Since the syntheses of vanadium phophitesin the presence of piperazinium cation as structural director by Zubieta et al., thegreat interest in the synthesis of new transition metal phosphites has been aroused.Up to date, transition metal phosphites have been extensively studied, the compoundsof V(III), Fe(III), Co(II), Mn(II), Zn(II) and Cr(III) with their various properties havebeen reported. Organically-templated main block metal phophites [NH2(CH2)6NH2][Al(OH)(H(HPO3))2] was prepared. In this thesis, we described the synthesis,crystal structure and some properties of a series of metal phosphite compounds. i摘要 吉林大学博士学位论文 Using 1,2-diammonium-propane as structure-directing agent, a two-dimensionalzincophophites have been synthesized under mild hydrothermal conditions. Itpossesses a layered architecture and organic template molecules located between theinorganic layers forming hydrogen bonds. The inorganic layers, which consist of 4,8-membered rings, are constructed of alternating ZnO4 tetrahedra and [HPO3 ] 2-pseudo pyramid by sharing vertices. Each 4-membered ring is capped by a [HPO3 ] 2-pseudo pyramid. The 1,2-diammonium-propane template molecules are locatedabove the eight-membered rings. Using 1,4- diacyclohexane and 1,6-diaminohexane 1,2-mmonium-propane asstructure-directing agent, two zincophophites possessed the samillar structure havebeen synthesized under mild hydrothermal conditions. They are both built up fromthree-dimensional Zn/P/O frameworks. Corner-linked ZnO4 tetrahedra and [HPO3 ] 2-pseudo pyramids form 4,6,8-membered rings and 12-membered ring channels.N,N,N',N'?tetramethylenediamine and DABCO as structure-directing agent, twozincophophites possessed novel structure have been synthesized under mildhydrothermal conditions. A novel three-dimensional zincophosphite templated byN,N'-dimethylpiperazine, [C6H16N2]·Zn3(HPO3)4 with helical chains, has beensynthesized under mild mixed solvothermal conditions and characterized by X-raycrystallography, differential thermal-thermogravimetric analysis (TG-DTA), 31PMAS NMR spectrum and IR spectroscopy. The structure consists of a network ofstrictly alternating ZnO4 tetrahedra and [HPO3 ] pseudo pyramid forming tripled 2-4-membered ring chains. This compound exhibits a three-dimensional structure with8-membered ring channels where the completely protonatedN,N'-dimethylpiperazine cations are located. Under mild hydrothermal conditions, using imidazole and guanidinium asstructure-directing agent, two vanadium phosphate-phosphites were synthesized andcharacterized by single crystal X-ray diffraction, IR spectroscopy, inductivelycou...