Synthesis, structure and properties of three novel transition-metal-containing tantalum-phosphate clusters

Peroxide ligation of aqueous metal–oxo clusters provides rich speciation and structural diversity. Here, three novel transition-metal derivatives of polyoxometalate anions, [Ni2(H2O)10{P4Ta6(O2)6O24}]6–(1a), [Zn(H2O)4{P4Ta6(O2)6O24}]8–(2a) and [Cd(H2O)4{P4Ta6(O2)6O24}]8–(3a), have been successfully synthesized by adopting a one-pot reaction strategy. All of these hexatantalates are built from a new-type phosphorus-incorporated hexatantalates. We investigated the solution behaviors, and the peak assignments of the MS spectra indicated some degree of stability of them in water. Furthermore, the proton-conducting ability of compound 1a was also explored and it has shown well conductivity at high relative humidities, with conductivity achieved 1.22 × 10–3S/cm (85 °C, 90%RH).