Pervaporation membranes in direct methanol fuel cells

Pivovar, Bryan S.; Wang, Yuxin; Cussler, E. L.

doi:10.1016/s0376-7388(98)00264-6

Cited by 394 publications

(231 citation statements)

References 11 publications

Supporting

Mentioning

223

Contrasting

Unclassified

Order By: Relevance

“…44 Among the most significant of Nafion's drawbacks is its high methanol crossover in the DMFC application. This limitation is associated with the microstructure of Nafion, where interconnected ionic domains strongly contribute to its high proton conductivity, but at the same time contribute to fast methanol diffusion.…”

Section: Resultsmentioning

confidence: 99%

Aromatic Poly(ether ketone)s with Pendant Sulfonic Acid Phenyl Groups Prepared by a Mild Sulfonation Method for Proton Exchange Membranes

et al. 2007

View full text Add to dashboard Cite

The sulfonation selectivity of seven poly(ether ether ketone)s (PEEKs) was investigated, and several possessed targeted single-or double-substituted sites per repeated unit on pendant phenyl groups via the postsulfonation approach. The presence of the various pendant groups enabled postsulfonation to occur under mild reaction conditions, in much shorter times than required for the sulfonation of commercial PEEK. A series of poly(ether ketone)s (PEKs) with ion exchange capacity of 2.23-0.84 mequiv/g could be realized by controlling the length of unsulfonated segments of both homopolymers and copolymers. These side-group sulfonation polymers had excellent mechanical properties, good thermal and oxidative stability, and good dimensional stability in hot water. The methanol permeability values of Me-SPEEKK, Me-SPEEKDK, Ph-SPEEKK, and Ph-SPEEKDK at room temperature were in the range 3.31 × 10 -7 -9.55 × 10 -8 cm 2 /s, which is several times lower than that of Nafion 117. Me-SPEEKK and Ph-SPEEKK also exhibited high proton conductivity of 0.15 S/cm at 100°C, which is higher than that of Nafion 117. Transmission electron microscopy analysis was used to observe their microstructure for evidence of microphase separation of ionic and hydrophobic domains. The results showed these side-group-acid materials are possible inexpensive candidate materials for proton exchange membranes in fuel cell applications.

show abstract

Section: Resultsmentioning

confidence: 99%

Aromatic Poly(ether ketone)s with Pendant Sulfonic Acid Phenyl Groups Prepared by a Mild Sulfonation Method for Proton Exchange Membranes

et al. 2007

View full text Add to dashboard Cite

show abstract

“…The membranes having a combination of high proton conductivity and low methanol crossover are being pursued for DMFC system. It is facile to evaluate the membranes through drawing a performance trade-off plot containing both methanol permeability and proton conductivity [26]. As shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

Enhanced thermo-oxidative stability of sulfophenylated poly(ether sulfone)s

Liu

Robertson

Kim

et al. 2010

Polymer

View full text Add to dashboard Cite

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. Monophenylated poly(ether sulfone)s (Ph-PES) and diphenylated poly(ether sulfone)s (DiPh-PES), were synthesized as starting materials for the preparation of sulfonated polymers with well-defined chemical structure. Mild post-polymerization sulfonation conditions led to sulfonated Ph-PES (Ph-SPES) bearing acid groups on both the pendant phenyl group and the backbone, and sulfonated DiPh-PES (DiPh-SPES) bearing acid groups only on the two pendant phenyl groups. Both series of polymers had excellent mechanical properties, high glass transition temperatures, good thermal and oxidative stability, as well as good dimensional stability. It is interesting to note that exclusively pendant-phenyl-sulfonated (bissulfophenylated) DiPh-SPES copolymers possessed obviously better thermal and oxidative stability compared with the corresponding pendant-phenyl-sulfonated/main-chain-sulfonated Ph-SPES copolymers. The methanol permeability values of the membranes were in the range of 7.0 Â 10 À7 -9.4 Â 10 À8 cm 2 /s at 30 C, which is several times lower than that of Nafion 117. DiPh-SPES-50 and Ph-SPES-40 also exhibited high proton conductivity (approximately 0.13 S/cm at 100 C).

show abstract

“…Indeed, a high methanol permeability is the common drawback of all the membranes used nowadays in DMFCs, i.e. perfluorosulfonated ionomers (PFSI), such as Nafion ® , sulfonated polyaromatics, including polysulfone (PSUs) [2,3], polyetheretherketone (SPEEK) [4,5] and polyphenylene oxide (SPPO) [6], and polybenzimidazole [7,8]. The main strategy used until now toovercome this problem consists in dispersing inorganic fillers, such as silica [9], heteropolyacid [10,11], and zirconium phosphate [12] within the polymer.…”

Section: Introductionmentioning

confidence: 99%

Contribution of nanoclays to the barrier properties of a model proton exchange membrane for fuel cell application

Thomassin

Pagnoulle

Caldarella

et al. 2006

Journal of Membrane Science

View full text Add to dashboard Cite

Direct methanol fuel cells (DMFCs) that use a proton exchange membrane (PEM) as electrolyte, is a promising alternative source of energy for the future. However, methanol crossover from the anodic side to the cathodic one is a major problem in DMFC. Proper dispersion of layered silicates within the fuel cell membrane has been proposed as a strategy for improving the barrier properties of the membrane. The validity of this approach has been tested in case of a model membrane consisting of phosphotungstic acid doped poly(vinyl alcohol). A solvent casting technique has been used, which allows the nanofiller to be delaminated by an ultrasonic pretreatment, as confirmed by TEM and XRD analysis. The layered silicates have a favourable impact on the methanol permeability, whose the decrease overcompensates some loss in ionic conductivity.

show abstract

Pervaporation membranes in direct methanol fuel cells

Cited by 394 publications

References 11 publications

Aromatic Poly(ether ketone)s with Pendant Sulfonic Acid Phenyl Groups Prepared by a Mild Sulfonation Method for Proton Exchange Membranes

Aromatic Poly(ether ketone)s with Pendant Sulfonic Acid Phenyl Groups Prepared by a Mild Sulfonation Method for Proton Exchange Membranes

Enhanced thermo-oxidative stability of sulfophenylated poly(ether sulfone)s

Contribution of nanoclays to the barrier properties of a model proton exchange membrane for fuel cell application

Contact Info

Product

Resources

About