Hydrothermal Synthesis, Structural Characterization and Proton-conducting Property of a 3-D Framework Based on Zr3Na3-Substituted Polyoxometalate Building Blocks

摘要

A novel Zr-substituted polyoxometalate(POM) H_2K_3[Na_6(H_2O)_9][Zr_3Na_3O_3(H_2O)_3-(GeW_9O_(34))_2]·12H_2O(1) has been made under hydrothermal conditions. 1 was characterized by infrared spectrum, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Crystal data are: H_(50)O_(95)Na_9K_3Ge_2Zr_3W(1)_8, hexagonal space group P63/mmc, a = 15.2251(6), b = 15.2251(6), c = 25.035(2) ?, V = 5025.7(6) ?~3, Z = 2, D_c = 3.716 mg/m^3, μ = 21.648 mm^(-1), F(000) = 4726, the final R = 0.0259 and w R = 0.0647 for 1487 observed reflections with I > 2σ(I). Single-crystal X-ray structure analysis reveals that 1 exhibits a 3-dimensional framework structure based on Zr_3Na_3-substituted polyanions [Zr_3Na_3O_3(H_2O)3(GeW_9O_(34))_2]^(11-) and [Na_6(H_2O)_9]^(6+) clusters building blocks. UV-Vis spectrum indicates that 1 is a wide-gap semiconductor. In addition, the proton-conducting property of 1 was also investigated.