Continuous channels created by self-assembly of ionic cross-linked polysiloxane-Nafion nanocompositesElectronic supplementary information (ESI) available: Experimental section; solid-state NMR spectra; XPS spectra; ATR/FTIR spectra; oxidative stability and photos. See DOI: 10.1039/c2py20203d

Ionically cross-linked ionomers have been developed via sol-gel chemistry by introducing poly(vinylimidazole)-functionalized mercaptopropyltrimethoxysilane into Nafion. The cross-linked polysiloxane framework endows the membrane with homogeneity and good stability. The ionical cross-linking enables the self-assembly between the inorganic framework and Nafion, which produces concentrated and inter-connected channels. This structure offers a practicably effective blocking effect to minimize the methanol cross-over problem in DMFCs, and improves the power output by 35% in comparison with a commercial Nafion membrane. Continuous channels created by self-assembly of imidazole-anchored polysiloxane and Nafion were found to effectively enhance proton transportation.