| Microporous molecular sieves, such as zeolites, are one of the most important porous materials, which have wide usage in ion-exchange, catalysis, gas adsorption and separation, and microreactors etc, benefited from their highly ordered pore structures and good physical or chemical performance. Nowadays many efforts are focused on preparation of zeolite-type materials with new framework topologies or chemical compositions.Recently, germanate-based molecular sieves, including the pure germanates and ones containing metal ion in their frameworks, are one of the great interests in microporous and zeolite-analogous systems. Because germinates have more structural diversity of coordination chemistry compared with silicates, some of their frameworks are novel with fascinate features such as mixed Ge4+ coordination in ASU-14, helical pores in UCSB-7, 3-rings in UCSB-9 and 24-membered rings (MRs) large pores in FDU-4. However, the study of germanate-based molecular sieves is far from enough. In this dissertation we primarily study the hydro/solvothermal syntheses and structural characterization of open framework germanates and metal germanates with new structures. The following are the main results.In the germanate system, four new open framework germanate, including Ge5O5(OH)10·5H2O, (H3O)+K3Ge7O16·3H2O (FDG-1), K4Ge9O20 (FDG-2) and (C3H11N2)(OH)[Ge10O20], were obtained by using 4-(aminoethyl) pyridine, K+ and 1,4-diaminobutane as template respectively. Ge5O5(OH)10·5H2O has a layer structure with 3-MRs and 9-MRs which is similar to the structure of UCSB-9. FDG-1 and FDG-2 are the pharmocosiderite analogues which are both constructed from same rock-like second building units (SBUs) with the composition of Ge10O28, but different connection way of this SBUs lead to the different structures of them. For the (C3H11N2)(OH)[Ge10O20] it is the first germanate molecular sieve with zeotype AST topology.The investigation of relationship between the synthesis conditions and structures indicates that the amines and solvents have remarkable effect on the structures of germanates. The size and shape of amines are related to the pore or channel shape of the germanates. The structural directing role of alkali metal ions are generally strong than that of amine except for the piperazine and 1,3-diaminopropane. If Al3+ and Ga3+ is added to the reaction mixture they can be incorporated into the germanate frameworks and have effect on the structure formation. Compared with silicates system germanates are more easier to accommodate diamines and other muti-headed amine than silicates.In the zirconium germanate system, three novel open framework zirconogermanates, FDZG-1 ((C4N2H12)[ZrGe4O10F2]), FDZG-2 ((NH4)2ZrGe3O9), FDZG-3 ((H2DEA) H2O [ZrGe3O9]) and ASU-15 ((H2DAB)[ZrGe2O6F2]), were synthesized by a new synthetic method which uses ZrO(NO3)2-2H2O as source of Zr and organic amines as structure direct agents in hydrothermal conditions. Their structures are all based on the structural principle whereby germanate units such as cyclic trigermanate, germanate chain and germanate layer, are bridged by ZrO6 (or ZrO4F2) octahedrons to form frameworks; nonframework species such as pronated organic amine cations, waters or NH4+ ions fill the intracrystalline pore space. Their structures contain high proportion of 3-MRs.In the titanium germanate system, two novel organically templated titanogermanates, FDTG-1 ((C4H12N2)6[Ti12Ge22O80]) and FDTG-2 ((C6H22N4)2[Ti3Ge14O38]) were synthesized by using piperizine and tris (2-aminoenthyl) amine (TREN) as template. FDTG-1 has a layer structure, which is connected by titanogermanate clusters. [Ti12Ge20O56] and GeO4 octahedra, and piperazine molecules are contained between the layers. The 3D framework structure of FTG-2 is also built up by a titanogermanate clusters with the composition of [Ge 12Ti3O36], and the TREN molecules are situated in the channels playing a stable role.The syntheses of other metal germinates containing B, Al and Zn, were alsoexplored. And we got a...
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