Abstract

In the current study, a novel imidazole metal complex named diimidazole platinum diiodide (PtIm2I2) was prepared and then incorporated into Nafion-based proton exchange membrane (PEM). The composite membranes showed better proton conductivity performances than that of recast Nafion. The PtIm2I2/Nafion composite membrane with an optimized loading (0.5% (w/w)) of PtIm2I2 exhibited the proton conductivity as high as 0.11 S/cm at 80 °C under 40% relative humidity (RH), nearly 7 times higher than that of the recast Nafion (0.014 S/cm) under the same condition. First, the good affinity between imidazole groups of PtIm2I2 and the sulfonic acid groups of Nafion could effectively reduce the spatial hindrance of proton transport, consequently promoting the proton conductivity of the PtIm2I2/Nafion composite membrane greatly, especially under low-humidity conditions. Second, the increased water retention capability of the composite membrane derived from the strong H-bonding interaction between imidazole and H2O also benefited the enhancement of the proton transport. All these conclusions were confirmed by various characterizations, such as SEM, TEM, AFM, IR, TGA, XRD etc.

<<全文链接>>