Syntheses, Structures and Proton Conductivities of Two Complexes Based on Decorated Keggin-Type Clusters: {[M(dmphen)(DMF)2(H2O)]2[SiW12O40]}·6H2O (M = Cu and Zn; dmphen = 4,7-dimethyl-1,10-phenanthroline)

Abstract

Two proton-conductive complexes based-on decorated Keggin-type clusters, {[Cu(dmphen)(DMF)2(H2O)]2[SiW12O40]}·6H2O (1) and {[Zn(dmphen)(DMF)2(H2O)]2[SiW12O40]}·6H2O (2) (where dmphen is 4,7-dimethyl-1,10-phenanthroline and DMF is N,N-dimethylformamide), were simply synthesized by the reaction of H4SiW12O40·24H2O, CuCl2·6H2O/ZnCl2 and dmphen at room temperature. The products were structurally characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction analyses. Single-crystal X-ray diffraction analyses at 293 K revealed that two complexes both crystallized in the monoclinic space group C2/c and presented two three-dimensional supramolecular networks with one-dimensional hydrophilic channels constructed by decorated Keggin-type clusters and solvent water molecules via the hydrogen-bonding interactions. The results of thermogravimetric analyses suggest that two complexes have good water holding in one-dimensional hydrophilic channels in the temperature range 20–100 °C. Two Complexes exhibit good proton conductivities (over 10−5 S cm−1 for 1 and over 10−4 S cm−1 for 2) at 100 °C in the relative humidity range 35–98%.