| In this work,all compounds were synthesized by using the same preparation method,namely hydrothermal method.By selecting different organic ligand molecules and transition metal raw materials to modify POM anions,thirteen compounds based on Keggin and its vacant sandwich-type,Anderson type and homopolymolybdate were successfully synthesized through adjusting the conditions of the reaction system.These thirteen compounds were characterized by X-ray single crystal diffraction,infrared spectroscopy,X-ray powder diffraction and other characterization methods.In addition,we have also carried out research on various practical properties of these novel POM functional compounds,such as electrochemical and photocatalytic properties.1.By using two organic raw materials 1,2-diphenyl-ethane-1,2-dione(ded)and benzene-1,2-diamine(bdm)under hydrothermal conditions,a Keggin-based compound modified by a big planar conjugated ligand was successfully synthesized,with the reactants ded and bdm converting into ligands L1and L2in situ by hydrothermal technique.Compound 1 shows a 3D framework with the 2D POM-based layers linked by Na and Ag5 atoms.In addition,the electrochemical and photocatalytic properties of this compound were also explored.Compound 1can be used as a kind of POM-based electrocatalyst for the electrochemical reduction of CO2with a high Faraday efficiency,which is rarely observed in PMo12-based compounds.[AgI11Na3(L1)4(L2)2(H2O)4(PMo9VIMo3VO40)2](1)L1=1H-1,2,3,5,10-pentaheterocyclic[b]anthracene-4,11-dioneL2=6-nitro-1H-benzotriazole2.By using triazole ligands 3-[1,2,4]triazole-4-methyl-benzylamine(L3)and1,3-bis(1,3,4-triazole-1-methyl)benzene(L4),four POM-based compounds were synthesized under hydrothermal conditions.Compound 2 is based on the homopolymolybdate anions;compounds 3 and 4 are isostructural containing the same Anderson type anions;compound 5 is a{PMo6O24N4}-based compound functionalized by organic molecules.The Mo-N bonds assit the construction of{PMo6O24N4}subunit.In addition,the photocatalytic,electrocatalytic and fluorescence sensing properties of compound 5 were studied.[Cd2?(L3)2(H2O)6(?-Mo8O26)0.5]·3H2O(2){Co2?(L3)2[H2(?-TeMo6O24)]}(3){Cu2?(L3)2[H2(?-TeMo6O24)]}(4){[Cd3?(H2O)8]·[H4PMo6O24(L4)]2}·H2O(5)L3=3-[1,2,4]triazole-4-methyl-benzylamineL4=1,3-bis(1,3,4-triazole-1-methyl)benzene3.By using the ligands 3,5-bis-(2,5-dihydro-imidazol-1-yl)-benzoic acid(L5)and 2,5-bis-(2,5-dihydro-imidazol-1-yl)-terephthalic acid(L6)respectively containing imidazole and carboxylic acid groups,eight POM-based compounds6-13 were synthesized by hydrothermal method.The N donor in imidazole group and the O donors in carboxylic acid group of organic ligands L5and L6can coordinate with transition metal atoms to construct novel POM-based compounds.Compounds 6-13 are based on the structure of Keggin and homopolymolybdate.And we also selectively discussed the electrochemical behavior and photocatalytic properties of 6-13.{Co2?(H2O)4(L5)2[H2(?-Mo8O26)]}·H2O(6){Cd2?(H2O)4(L5)2[H2(?-Mo8O26)]}·H2O(7){Cu2?(H2O)4(L5)2[H2(?-Mo8O26)]}·H2O(8){Ni ?(H2O)2(L5)[H2(?-Mo8O26)]0.5}(9){Zn ?(H2O)2(L5)[H2(?-Mo8O26)]0.5}(10)[Zn3?(L6)3(H2O)3(PMo12O40)]·3H2O(11)[Cd ?(L5)2(HPMo12O40)]·2H2O(12){Fe2?(H2O)4(L5)2[H2(?-Mo8O26)]}·H2O(13)L5=3,5-bis-(2,5-dihydro-imidazol-1-yl)-benzoic acidL6=2,5-bis-(2,5-dihydro-imidazol-1-yl)-terephthalic acid... |
PDF Full Text Request