Perfluorosulfonic acid short side chain

Kreuer et al. [25] investigated the membrane properties, including water sorption, transport (proton conductivity, electro-osmotic water drag and water diffusion), microstructure and viscoelasticity of the short-side-chain (SSC) perfluorosulfonic acid ionomers (PFSA, Dow 840 and Dow 1150) with different lEC-values. The data were compared to those for Nafion 117, and the implications for using such ionomers as separator materials in direct methanol and hydrogen fuel cells discussed. Tire major advantages of PFSA membranes were seen to be (i) a high proton conductivity. 

Z.D. Deng and K.A. Mauritz, Dielectric relaxation studies of acid-containing short-side-chain perfluorosulfonate ionomer membranes, Macromolecules, 1992, 25, 2369-2380. 

Wu D, Paddison S J and Elliott J A (2009), Effect of Molecular Weight on Hydrated Morphologies of the Short-Side-Chain Perfluorosulfonic Acid Membrane , Macromolecules, 42,3358-3367. 

K.D. Kreuer, M. Schuster, B. Obliers, O. Diat, U. Traub, A. Fuchs, U. Klock, S.J. Paddison, J. Maier, Short-side-chain proton conducting perfluorosulfonic acid ionomers why they perform better in PEM fuel cells, J. Power Sources 178 (2008) 499-509. 

Cui and co-workers performed classical molecular-dynamics simulations of two dilferent perfluorosulfonic-acid (PFSA) membranes to investigate the hydrated morphology and the hydronium-ion dilfusion. They put special emphasis on the water content of the membrane (5% to 20%) and compared the properties for two dilferent lengths of the side chains carrying the sulfonic-acid groups. The short side chains lead to a more disperse distribution of water clusters inside the membrane. At low water content this results in a more connected water-channel network, which enhances the proton transport. 

This chapter reviews characteristics and performance of modified sulfonic acid-based membranes, particularly composite membranes including inorganic fillers and short-side chain perfluorosulfonic membranes for intermediate temperature applications. The characteristics of these systems for operation in direct alcohol fuel cells, in polymer membrane (PEM) electrolyser and automotive PEM fuel cells are analyzed. 

Aquivion E87-12S short-side chain perfluorosulfonic acid (SSC-PFSA) membrane with equivalent weight (EW) of 870 g eq and 120 pm thickness produced by Solvay Specialty Polymers was tested in a polymer electrolyte membrane water electrolyser (PEMWE) and compared to a benchmark Nation N115 membrane (EW 1100 g eq ) of similar thickness [27]. Both membranes were tested in conjunction with in-house prepared unsupported Ir02 anode and carbon-supported Pt cathode electrocatalyst. The electrocatalysts consisted of nanosized Ir02 and Pt particles (particle size 2-4 nm). The electrochemical tests showed better water splitting performance for the Aquivion membrane and ionomer-based membrane-electrode assembly (MEA) as compared to Nafion (Fig. 2.21). Lower ohmic drop constraints and smaller polarization resistance were observed for the electrocatalyst-Aquivion ionomer interface indicating a better catalyst-electrolyte interface. A current density of 3.2 A cm for water... 

Siracusano S, Baglio V, Stassi A et al (2014) Performance analysis of short-side-chain Aquivion perfluorosulfonic acid polymer for proton exchange membrane water electrolysis. J Membr Sci 466 1-7... 

Zhang YM, Li L, Tang JK, Bauer B, Zhang W et al. (2009) Development of covalently cross-linked and composite perfluorosulfonic acid membranes . ECS Trans. 25 1469. Gao HR, Jones DJ, Roziere J, Zhang YM (2011) Cross-linking of the short-side-chain perfluorosulfonic acid ionomer . Manuscript in preparation. 

Wu D, Paddison SJ, Elliott JA (2009) Effect of molecular weight on hydrated morphologies of the short-side-chain perfluorosulfonic acid membrane . 

Kreuer, K. D., Schuster, M., Obhers, B., Diat, O., Traub, U., Fuchs, A., Klock, U., Paddison, S. J., and Maier, J. 2008. Short-side-chain proton conducting perfluorosulfonic acid ionomers Why they perform better in PEM fuel cells. 178(2), 499-509. 

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