Synthesis, Structures And Properties Of Metal-organic Frameworks Based On Ligands Containing Phosphorus

Metal organic frameworks (MOFs), which emerged as an extensive class of porous materials with ultrahigh porosity and enormous internal surface areas, are constructed by organic ligands (as linkers) and metal ions or metal clusters (as nodes), which forms coordination bond by self-assemble. The structures of MOFs are diversiform and controllable, since both the organic and inorganic constituents can be regulated, which makes MOFs of interest for potential applications in gas storage and separation, luminescent, catalysis, and proton conductivity. Choosing proper ligands is significant for the target MOFs’structures and properties, carboxylate-based MOFs have been demonstrate to have high surface area and uniform pore size distribution, but their lack of stability in air and water. Meanwhile, N-heterocycle-based MOFs is other type of MOFs which is more robust. So far. there other type of MOFs which is based phosphonate ligands attracted intensive attention for phosphonates form stronger bonds than carboxylates do with metal atoms. These materials are poorly crystalline but show great thermal stability and are insoluble even in highly acidic media. In this thesis, based on two ligands containing phosphorus, we have constructed a series of MOFs materials by solvothermal method, and studied its structures and adsorption properties.1.A V-shaped ligand containing phosphorus (H3hpda) was successfully synthesized, and three MOFs based on it formulated as [Cu3(hpda)2·DMF-2H2O]·3DMF·H2O (1), [Mg3(μ2-OH2)2(OH2)2(hpda)2]·3DMF·2H2O(2), [Co(hpda)]·[NH2(CH3)2]·2DMF·3H2O (3), [Mn3(hpda)2·DMF·H2O]·DMF H2O (4) were synthesized by solvothermal method. These MOFs are both 3D networks with 1D channel.1 not only exhibits excellent performances of uptake CO2 and C1-C2 light hydrocarbons (methane, ethane, ethylene, acetylene), but also shows high selectivity of C2 light hydrocarbons (ethane, ethylene, acetylene) and CO2 with respect to methane.2.Another V-shaped ligand containing phosphorus 5,5’-(hydroxyphosphoryl)diisophthalic acid (H5hpdia) was successfully synthesized, and two MOFs based on it formulated as [Zn4·2(hpdia)]·2[NH2(CH3)2]·3DMF·4H2O (5), [Cu2(Hhpdia)·2H2O]·3DMF·9H2O(6)were synthesized by solvothermal method. 5 is 3D networks with 1D channel exhibits excellent performances of uptake CO2 and C1-C3 light hydrocarbons (methane, ethane, ethylene, acetylene, propane), but also shows high selectivity of C2-C3 light hydrocarbons (ethane, ethylene, acetylene, propane) and CO2 with respect to methane. And the structure of 6 which contains two type cages is highly porous.