A stable polyoxometalate-based porous coordination polymer with high proton conductivity

摘要

A new coordination polymer based on the Keggin-type [SiW12O40](4-), namely, [Cu4L2(SiW12O40)(OH)(4)(H2O)(8)]8H(2)O (1), has been prepared by a hydrothermal method (L = 1,4-bis(4H-1,2,4-triazol-4-yl)benzene). The supramolecular framework of 1 is constructed from two dimensional Cu-L layers. Compound 1 was found to be stable in aqueous solutions having pH values ranging from 1 to 13 as well as some other boiling solvents, such as boiling water, methanol and ethanol. Compound 1 exhibits a proton conductivity of 1.4 x 10(-4) S cm(-1) at 65 degrees C and 98% RH. More importantly, the proton conductivity of 1 presents a 28-fold enhancement (3.9 x 10(-3) S cm(-1) at 65 degrees C and 98% RH) by immersing its gourd-shaped channels into N2H4H2SO4.