Hydrothermal Syntheses,Crystal Structures And Properties Of Metal Phosphites/Organic Phosphates

Microporous materials have attracted considerable research interest owing to their rich structural chemistry and potential applications in catalysis, gas storage, adsorption and separation. Compared with the 4-connected phosphate, the 3-connected phosphite features the blocking model because one site is occupied by H atom, which is favorable for the fabrication of novel framework structures. Beside the connection of O atoms, the P atom of the organophosphonate acid is also connected with different functional groups containing coordination sites. The diversity of the organophosphonate holds great promise in the synthesis of new metal organophosphate. As an important organophosphonate, the flexible hydroxyethylidene diphosphonic acid(Hedp) exhibits various coordination mode, which provides possibility for the creation of novel open framework with interesting structure and/or properties. In this dissertation, hydrothermal synthesis was used to prepare five beryllophosphite/beryllophosphate templated by different organic amines and seven metal organophosphates with open architecture. The twelve synthesized compounds have been characterized by single-crystal X-ray diffraction, elemental analysis, IR, powder X-ray diffraction, thermogravimetric and fluorescence analysis. The main contents of this thesis are summarized as follows:1. Based on the assembly of beryllium sulfate tetra hydrate and phosphite/phosphate in the presence of different organic amines, we syntheize five beryllophosphate/beryllophosphate compounds under hydrothermal conditions. The protonated organic amines serves as structural-directing agents(SDAs) and exists in the void of the framework via guest-host interactions. Compound 3-1, a beryllium phosphate compound, contains a two-dimensional(2D) layer, while compound 3-2, a beryllium phosphate compound, displays a three-dimensional(3D) open-framework structure with 12-membered ring(12-MR) channels. Both 3-3 and 3-4 are beryllium phosphites and display the similar framework structure. The SDAs for 3-3 and 3-4 are 1,6-hexanediamine and 1,4-butanediamine, respectively. Compound 3-5 possesses 3D framework with 18-MR channels. It is the first beryllium phosphites that involves 18-MR large channels.2. Based on the assembly of hydroxyethylidene diphosphonic acid and zinc oxide in the presence of different organic amines, we prepare seven organophosphonate zinc compounds under hydrothermal conditions. Among them, compounds 4-1 and 4-2 are isostructural 2D layer. Compounds 4-3, 4-4, 4-5 show 3D open framework structure. The protonated organic amines not only balance framework charge but also act as structural-directing agents(SDAs). Compounds 4-6 and 4-7 are organic-inorganic hybrids, in which the organic ligands participate in the formation of the framework, via coordinating with metal ions. Compounds 4-6 shows 3D open-framework and compound 4-7 exhibits 2D layered structure.