Polyoxometalates (POMs) are discrete clusters of metal-oxide units, perhaps the largest nonbiologically derived molecules structurally characterized, with a large diversity of nanoscale structure and diverse properties. They are constructed from early transition metals in their highest oxidation states, most commonly vanadium, molybdenum and tungsten and less commonly niobium, tantalum and palladium. The polyanions are arranged as spherical, separate and compact units with high symmetry where electrostatic interactions are minimized. My lecture is divided into two section, synthesis and characterization of new polyoxometalates compounds and application of the polyoxometalates as catalyst and photo catalyst. In the first section, our earlier work, detail of synthesis, structure characterization and properties of new polyoxometalates compounds such as [MAs2W18U2O72]13- (M = NH4+, K+), [Na2As2W18U2O72]12-, [A--(SiW9O34)2(LnOH2)3CO3]13-, [(XW9O34)2(LnOH2)3(CO3)]11-, (SiLn2W10O38)4(OH)4(H2O)2(W3O8)]26-, Ln = lanthanide ions; X = P, Si, As, and H2[{M(H2O)8M(H2O)7M(H2O)6}P2W18Ce3O70(OH)(H2O)2]∙xH2O; M = Ce3+, Nd3+ and Sm3+ were reported. In the continue, my curent work, containing of the heterogenization or immobilization of suitable POMs onto/into various solid supports, such as titanium dioxide, magnetic nanoparticles and Layered Double Hydroxides (LDH) and metal organic frameworks (MOF) is were reported.
