Journal of Power Sources, Vol.196, No.14, 5803-5810, 2011
Hybrid proton conducting membranes based on sulfonated cross-linked polysiloxane network for direct methanol fuel cell
A series of novel hybrid membranes based on sulfonated poly(arylene ether ketone)s (SNPAEKs), polysiloxane (KH-560) and sulfonated curing agent (BDSA) has been prepared by sol-gel and cross-linking reaction for direct methanol fuel cells (DMFCs). All the hybrid membranes (SKB-xx) show high thermal properties and improved oxidative stability compared with the pristine SNPAEK membrane. The sulfonated cross-linked polysiloxanes networks in the hybrid membranes enhance the mechanical properties and reduce the swelling ratio. The swelling ratio of SKB-20 is 22%, which is much lower than that of the pristine SNPAEK (37%) at 80 degrees C. Meanwhile, SKB-xx membranes with greatly reduced methanol permeabilities show comparative proton conductivities to pristine SNPAEK membranes. Notably, the proton conductivities of SKB-5 and SKB-10 reach to 0.192 S cm(-1) and 0.179 S cm(-1) at 80 degrees C, respectively, which are even higher than the 0.175 S cm(-1) of SNPAEK. (C) 2011 Elsevier B.V. All rights reserved.