| Open-framework materials of metal phosphates have exhibited many fascinating structural features and potential applications in catalysis, separation, biology, electrical conductivity, magnetism and photochemistry. Particularly, metal phosphites are of interest because the existence of pseudo pyramidal HPO32- units in the framework can reduce the M-O-P connectivity and generate novel open frameworks. As a part of the renaissance in the study of open-framework metal phosphates, metal phosphites appear to show structural diversity and versatility similar to that of the phosphates. So far, series compounds of vanadium phosphite, iron phosphite, cobalt phosphite, manganese phosphite, zinc phosphite and chromic phosphite have been successfully synthesized, and their magnetic and luminescent properties have also been studied.This work focuses on the synthesis and characterization of new metal phosphites/phosphates in the hydrothermal or solvothermal system through selecting suitable templating agents. We aim to develop new bimetal phosphites and bimetal phosphates with novel framework architectures, study their potential applications in the photoluminescence, and futher conclude the formational regularities of them that will further assist in the rational design and synthesis of new microporous materials. Main results include:1. A layered zinc phosphate/phosphite [C6H12(NH3)2][Zn4(HPO3)2(PO4)2(H2O)2] (denoted as ZnHPO-CJ47) with unique luminescent and photoelectronic properties. Unlike the known luminescent open-framework materials with single wide emission band, ZnHPO-CJ47 exhibits strikingly strong blue emissions with multi resolved peaks, which is firstly observed in metal phosphates/phosphites. It shows p-type conduction character under negative electric-field strength. These properties may be caused by the complex lattice defects revealed by EPR studies. Under similar reaction system, two heteroatom incorporated derivatives [M2xZn2(1-x)(HPO3)2(PO4)2(H2O)2][C6H12(NH3)2] (M=Co/Mn) (ZnCoHPO-CJ47, ZnMnHPO-CJ47) with distinct luminescent property have been successfully synthesized. All of them emit blue light, the unique emission is caused by the complex lattice defects existed in the framework, and the incorporation of Co and Mn atoms into the framework may fill some defects, resulting in the decrease of the emission peaks and the blue shift of emission broad.2. Two new metal phosphates (Zn0.67Co0.33PO4H)8[(CH3)2NH]4 (ZnCoPO-CJ48) and (Zn2Mn1P3O12H)4[(CH3)2NHH3O]4 (ZnMnPO-CJ49) have been solventhermally synthesized. ZnCoPO-CJ48 is the first layered heteroatom incorporated zincophosphate with neutral framework, which is constructed by the connection of MO4 tetrahedra (M=Zn, Co) and PO3OH tetrahedra forming a novel 2-D sheet. And the structure is connected by the H-bonding between inorganic layer and template to formed pseudo 8-ring channels. Three-dimensional zinc-manganese phosphate ZnMnPO-CJ48 with 16-ring channels was obtained under the similar synthetic conditions. Its structure can be conceptually generated from the layered structure analogous of ZnCoPO-CJ48 connected by a 4-ring building unit. In this work, the synthetic conditions of these two compounds were discussed detailed.3. Three new open-framework zincophosphites ZnHPO-CJn (n=2, 3, 4) possessing desired extra-large 24-ring channels of ZnHPO-CJ1 have been successfully prepared through selecting computationally predicted organic amines, such as cyclohexanamine, cyclopentylamine and n-propylamine molecules as the templates or SDAs. Structure comparison of these compounds indicates that the organic amines influence the resulting structure symmetry, cell parameters, and the opening sizes through the size and shape control although they have similar templating abilities. 4. In the hydrothermal system, three new open-framework vanadium phosphate (VPO-1, 2, 3) possessing 24-ring large pore have been successfully synthesized using n-butylamine, propylamine and piperidine as the templates, respectively. These compounds possess isostructural three-dimensional (3D) open-framework structure with multi-directional intersecting 8-ring, 16-ring channels.5. The morphology control of ZnHPO-CJ2 crystal was investigated by microwave irradiation in mixed-solvents system through incorporation additional metal source. The results show that the microwave synthesis technology can greatly decrease the reaction time and obtaine pure, high-quality large single crystals of ZnHPO-CJ2. In mixed-solvents system, beside ZnHPO-CJ2, a zinc phosphite with one-dimensional can also be prepared.6. By using benzylamine as SDA, a new zinc phosphite (C7H10N)8[Zn4(HPO3)8] has been hydrothermally synthesized, and its structure and fluorescence properties have characterized. Its structure consists of ZnO4 and HPO3 basic building units. The ZnO4 tetrahedra and HPO3 pseudo pyramids are connected to form an infinite 1-D chain along c-axis. Protonated benzylamine cations were located on both sides of the 1-D inorganic chain through hydrogen bonds.
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