Proton conducting composite membranes from sulfonated polyether ether ketone and SiO₂

Abstract

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO₂ for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy silane(TEOS) by sol-gel method. The covalent crosslinking structure was formed between —SO₃H of SPEEK via SiO₂. The SEM images show that the interfacial compatibility of SPEEK and SiO₂ is improved obviously and SiO₂ disperses uniformly in the polymer matrix and the particle diameter of SiO₂ does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO₃H and SiO₂.

Keywords

direct methanol fuel cell / sulfonated polyether ether ketone / sol-gel method / proton conductivity / methanol permeability

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