US EPA

1445957 

Journal Article 

Cross-linked zwitterionic polyelectrolytes based on sulfonated poly(ether sulfone) with high proton conductivity for direct methanol fuel cells 

Chen, Lie; Sun, L; Zeng, R; Xiao, S; Chen, Y 

2012 

Yes 

Journal of Power Sources
ISSN: 0378-7753 

212 

13-21 

10.1016/j.jpowsour.2012.04.008 

WOS:000305592900002 

Hybrid cross-linked membranes of SPES/TEOS/TPABS for direct
methanol fuel cells (DMFCs) are synthesized by sulfonated poly(ether sulfone) (SPES),
tetraethoxysilane (TEOS) and a zwitterionic silica containing sulfonic acid and ammonium groups,
3-[[3-(triethoxysilyl)-propyl]amino]butane-1-sulfonic acid (TPABS) using a sol-gel process with
the goal of obtaining high proton conductivity, low methanol permeability and good stability.
Increasing the amount of inorganic zwitterionic TPABS produces membranes that become denser and
more uniform. The increasingly SO3-rich cross-linked networks consequently lead to higher proton
conductivity and lower methanol permeability. It should be noted that the proton conductivity
reaches as high as that of Nafio (R) n 117, whereas the methanol permeability is greatly reduced
by the formation of the cross-linked structures. Among these membranes, SPES/TEOS/TPABS-70 (70 wt
% of TPABS to SPES in the membrane matrix), shows the best performance with a proton conductivity
value of 7.24 x 10(-2) S cm(-1), methanol permeability value of 2.46 x 10(-7) cm(2) s(-1), ion-
exchange capacity value of 1.37 mequivg(-1) and a comparable selectivity parameter of 2.63 x 10
(5) S cm(-3) s. (C) 2012 Elsevier B.V. All rights reserved. 

Polyelectrolytes; Poly(ether sulfone); Zwitterion; Sol-gel