Polymer Composites for High-Temperature Proton-Exchange Membrane Fuel Cells

  • Xiuling Zhu
  • Yuxiu Liu
  • Lei Zhu


Recent advances in composite proton-exchange membranes for fuel cell applications at elevated temperature and low relative humidity are briefly reviewed in this chapter. Although a majority of research has focused on new sulfonated hydrocarbon and fluorocarbon polymers and their blends to directly enhance high temperature performance, we emphasize on polymer/inorganic composite membranes with the aim of improving the mechanical strength, thermal stability, and proton conductivity, which depend on water retention at elevated temperature and low relative humidity conditions. The polymer systems include perfluoronated polymers such as Nafion, sulfonated poly(arylene ether)s, polybenzimidazoles (PBI)s, and many others. The inorganic proton conductors are silica, heteropolyacids (HPA)s, layered zirconium phosphates, and liquid phosphoric acid. Direct use of sol-gel silica requires pressurization of fuel cells to maintain 100% relative humidity for high proton conductivity above 100°C. Direct incorporation of HPAs such as phosphotungstic acid (PTA) into polyelectrolyte membranes is capable of improving both proton conductivity and fuel cell performance above 100°C; however, they tend to leach out of the membrane whenever fuel cell flooding happens. To prevent HPA leaching, amine-functionalized mesoporous silica is used to immobilize PTA in Nafion membranes, whose proton conductivity and fuel cell performance are discussed. Compared with Nafion, sulfonated poly(arylene ether)s such as sulfonated poly(arylene ether sulfone)s are cost-effective materials with excellent thermal and electrochemical stability. Their composites with HPAs show increased proton conductivity at elevated temperatures when fully hydrated. Organic/inorganic hybrid membranes from acid-doped PBIs and other polymers are also discussed.


Fuel Cell Proton Conductivity Arylene Ether Zirconium Phosphate Fuel Cell Performance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors appreciate the financial support of this work by U.S. Army Phase II portable fuel cell program through Connecticut Global Fuel Cell Center at the University of Connecticut. We also appreciate the partial support of this work from National Science Foundation of China (grant no. 50373005). The authors are grateful to Dr. Ruichun Jiang (Chemical Engineering Department at University of Connecticut) for the assistance in the fuel cell performance tests and cyclic voltametry study. Helpful discussions with Prof. James M. Fenton (Central Florida University) and Prof. H. Russell Kunz (University of Connecticut) are also acknowledged.


  1. 1.
    K. D. Kreuer, On the development of proton conducting polymer membranes for hydrogen and methanol fuel cells, J. Membr. Sci. 185, 29–39 (2001).CrossRefGoogle Scholar
  2. 2.
    G. Alberti, M. Casciola, L. Massinelli and B. Bauer, Polymeric proton conducting membranes for medium temperature fuel cells (110–160°C), J. Membr. Sci. 185, 73–81 (2001).CrossRefGoogle Scholar
  3. 3.
    L. E. Karlsson and P. Jannasch, Sulfone ionomers for proton-conducting fuel cell membranes 2. Sulfophenylated polysulfones and polyphenylsulfones, Electrochim. Acta 50, 1939–1946 (2005).CrossRefGoogle Scholar
  4. 4.
    Y. Yin, S. Hayashi, O. Yamada, H. Kita and K. -I. Okamoto, Branched/crosslinked sulfonated polyimide membranes for polymer electrolyte fuel cells, Macromol. Rapid Commun. 26, 696–700 (2005).CrossRefGoogle Scholar
  5. 5.
    T. Watari, J. Fang, K. Tanaka, H. Kita, K. -I. Okamoto and T. Hirano, Synthesis, water stability and proton conductivity of novel sulfonated polyimides from 4,4-bis(4-aminophenoxy) biphenyl-3,3′-disulfonic acid, J. Membr. Sci. 230, 111–120 (2004).CrossRefGoogle Scholar
  6. 6.
    S. Sundar, W. Jang, C. Lee, Y. Shul and H. Han, Crosslinked sulfonated polyimide networks as polymer electrolyte membranes in fuel cells, J. Polym. Sci. Part B: Polym. Phys. 43, 2370–2379 (2005).CrossRefGoogle Scholar
  7. 7.
    K. Miyatake, H. Iyotani, K. Yamamoto and E. Tsuchida, Synthesis of poly(phenylene sulfide sulfonic acid) via poly(sulfonium cation) as a thermostable proton-conducting polymer, Macromolecules 29, 6969–6971 (1996).CrossRefGoogle Scholar
  8. 8.
    K. Miyatake, E. Shouji, K. Yamamoto and E. Tsuchida, Synthesis and proton conductivity of highly sulfonated poly(thiophenylene), Macromolecules 30, 2941–2946 (1997).CrossRefGoogle Scholar
  9. 9.
    M. A. Hickner, H. Ghassemi, Y. S. Kim, B. R. Einsla and J. E. McGrath, Alternative polymer systems for proton exchange membranes (PEM)s, Chem. Rev. 104 4587–4612 (2004).CrossRefGoogle Scholar
  10. 10.
    F. Wang, M. Hickner, Y. S. Kim, T. A. Zawodzinski and J. E. McGrath, Direct polymerization of sulfonated poly(arylene ether sulfone) random (statistical) copolymers: Candidates for new proton exchange membranes, J. Membr. Sci. 197, 231–242 (2002).CrossRefGoogle Scholar
  11. 11.
    Y. S. Kim, F. Wang, M. Hickner, S. Mccartney, Y. T. Hong, W. Harrison, T. A. Zawodzinski and J. E. McGrath, Effect of acidification treatment and morphological stability of sulfonated poly(arylene ether sulfone) copolymer proton-exchange membranes for fuel-cell use above 100°C, J. Polym. Sci. Part B: Polym. Phys. 41, 2816–2828 (2003).CrossRefGoogle Scholar
  12. 12.
    S. Granados-Focil and M. H. Litt, A new class of polyelectrolytes, polyphenylene sulfonic acid and its copolymers, as proton exchange membranes for PEMFC's, Prepr. Symp. (Div. Fuel Chem., Am. Chem. Soc.) 49(2), 528–529 (2004).Google Scholar
  13. 13.
    S. Granados-Focil and M. H. Litt, Novel highly conductive poly(phenylene sulfonic acid)s and its evaluation as proton exchange membranes for fuel cells, PMSE Prepr. (Div. Polym. Mater. Sci. Eng., Am. Chem. Soc.) 89, 438–439 (2003).Google Scholar
  14. 14.
    J. Kerres, A. Ullrich, F. Meier and T. Haring, Synthesis and characterization of novel acid—base polymer blends for application in membrane fuel cells, Solid State Ionics 125, 243–249 (1999).CrossRefGoogle Scholar
  15. 15.
    K. D. Kreuer, A. Fuchs, M. Ise, M. Spaeth and J. Maier, Imidazole and pyrazole-based proton conducting polymers and liquids, Electrochim. Acta 43, 1281–1288 (1998).CrossRefGoogle Scholar
  16. 16.
    C. Yang, P. Costamagna, S. Srinivasan, J. Benziger and A. B. Bocarsly, Approaches and technical challenges to high temperature operation of proton exchange membrane fuel cells, J. Power Sources 103, 1–9 (2001).CrossRefGoogle Scholar
  17. 17.
    M. Yamada and I. Honma, Anhydrous proton conducting polymer electrolytes based on poly(vinylphosphonic acid)-heterocycle composite material, Polymer 46, 2986–2992 (2005).CrossRefGoogle Scholar
  18. 18.
    R. M. Acheson, An Introduction to the Chemistry of Heterocyclic Compounds, 3rd edn., Wiley, New York, (1976).Google Scholar
  19. 19.
    S. Malhotra and R. Datta, Membrane-supported nonvolatile acidic electrolytes allow higher temperature operation of proton-exchange membrane fuel cells, J. Electrochem. Soc. 144, L23–L26 (1997).CrossRefGoogle Scholar
  20. 20.
    Q. Li, R. He, J. O. Jensen and N. J. Bjerrum, PBI based polymer membrane for high temperature fuel cells-preparation, characterization and fuel cell demonstration, Fuel Cells 4(3), 147–159 (2004).CrossRefGoogle Scholar
  21. 21.
    R. He, Q. Li, G. Xiao and N. J. Bjerrum, Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic proton conductors, J. Membr. Sci. 226, 169–184 (2003).CrossRefGoogle Scholar
  22. 22.
    Y. S. Kim, F. Wang, M. Hickner, T. A. Zawodzinski and J. E. McGrath, Fabrication and characterization of heteropolyacid (H3PW12O40)/directly polymerized sulfonated poly(arylene ether sulfone) copolymer composite membranes for higher temperature fuel cell applications, J. Membr. Sci. 212, 263–282 (2003).CrossRefGoogle Scholar
  23. 23.
    B. Smith, S. Sridhar and A. A. Khan, Proton conducting composite membranes from polysulfone and heteropolyacid for fuel cell applications, J. Polym. Sci. Part B: Polym. Phys. 43, 1538–1547 (2005).CrossRefGoogle Scholar
  24. 24.
    S. M. J. Zaidi, S. D. Mikhailenko, G. P. Robertson, M. D. Guiver and S. Kaliaguine, Proton conducting composite membranes from polyether ether ketone and heteropolyacids for fuel cell applications, J. Membr. Sci. 173, 17–34 (2000).CrossRefGoogle Scholar
  25. 25.
    K. D. Kreuer, Proton conductivity: materials and applications, Chem. Mater. 8, 610–641 (1996).CrossRefGoogle Scholar
  26. 26.
    M. Watanabe, H. Uchida, Y. Seki, M. Emori and P. Stonehart, Self-humidifying polymer electrolyte membranes for fuel cells, J. Electrochem. Soc. 143, 3847–3852 (1996).CrossRefGoogle Scholar
  27. 27.
    P. L. Antonucci, A. S. Arico, P. Creti, E. Ramunni and V. Antonucci, Investigation of a direct methanol fuel cell based on a composite Nafion®-silica electrolyte for high temperature operation, Solid State Ionics 125, 431–437 (1999).CrossRefGoogle Scholar
  28. 28.
    K. A. Mauritz, I. D. Stefanithis, S. V. Davis, R. W. Scheez, R. K. Pope, G. L. Wilkes and H. H. Huang, Microstructural evolution of a silicon-oxide phase in a perfluorosulfonic acid ionomer by an in-situ sol-gel reaction, J. Appl. Polym. Sci. 55, 181–190 (1995).CrossRefGoogle Scholar
  29. 29.
    K. T. Adjemian, S. Srinivasan, J. Benziger and A. B. Bocarsly, Investigation of PEMFC operation above 100°C employing perfluorosulfonic acid silicon oxide composite membranes, J. Power Sources 109, 356–364 (2002).CrossRefGoogle Scholar
  30. 30.
    P. Costamagna, C. Yang, A. B. Bocarsly and S. Srinivasan, Nafion® 115/zirconium phosphate coposite membranes for operation of PEMFC above 100°C, Electrochim. Acta 47, 1023–1033 (2002).CrossRefGoogle Scholar
  31. 31.
    B. Ruffmann, H. Silva, B. Schulte and S. P. Nunes, Organic/inorganic composite membranes for application in DMFC, Solic State Ionics 162–163, 269–275 (2003).CrossRefGoogle Scholar
  32. 32.
    Y. Si, H. R. Kunz and J. M. Fenton, Nafion-Teflon-Zr(HPO4)2 composite membranes for high-temperature PEMFCs, J. Electrochem. Soc. 151, A623–A631 (2004).CrossRefGoogle Scholar
  33. 33.
    N. H. Jalani, K. Dunn and R. Datta, Synthesis and characterization of Nafion®-MO2 (M = Zr, Si, Ti) nanocomposite membranes for higher temperature PEM fuel cells, Electrochim. Acta 51, 553–560 (2005).CrossRefGoogle Scholar
  34. 34.
    T. Thampan, N. H. Jalani, P. Choi and R. Datta, Systematic approach to design higher temperature composite PEMs, J. Electrochem. Soc. 152, A316–A325 (2005).CrossRefGoogle Scholar
  35. 35.
    B. R. Ezzell, W. P. Carl and W. A. Mod, Preparation of vinyl ethers, U.S. Patent 4, 358–412 (1982).Google Scholar
  36. 36.
    S. J. Paddison and J. A. Elliott, Molecular modeling of the short-side-chain perfluorosulfonic acid membrane, J. Phys. Chem. A 109, 7583–7593 (2005).CrossRefGoogle Scholar
  37. 37.
    Y. Liu, Organic/inorganic composite membranes for high temperature proton exchange membrane fuel cells, M.S. Dissertation, University of Connecticut, USA, 2005.Google Scholar
  38. 38.
    Y. Liu, H. R. Kunz, J. M. Fenton and L. Zhu, Development of nafion/SiO2/phosphotunstic acid nanocomposite membranes for high temperature proton exchange membrane fuel cells, PMSE Prepr. (Div. Polym. Mater. Sci. Eng., Am. Chem. Soc.) 93, 703–704 (2005).Google Scholar
  39. 39.
    D. Zhao, Q. Huo, J. Feng, B. F. Chmelka and G. D. Stucky, Nonionic triblock and star diblock copolymer and oligomeric surfactant syntheses of highly ordered, hydrothermally stable, mesoporous silica structures, J. Am. Chem. Soc. 120, 6024–6036 (1998).CrossRefGoogle Scholar
  40. 40.
    X. Feng, G. E. Fryxell, L. Q. Wang, A. Y. Kim, J. Liu and K. M. Kemner, Functionalized monolayers on ordered mesoporous supports, Science 276, 923–926 (1997).CrossRefGoogle Scholar
  41. 41.
    Y. S. Kim, F. Wang, M. Hickner, T. A. Zawodzinski and J. E. McGrath, Heteropolyacid/sulfonated poly(arylene ether sulfone) composites for proton exchange membranes fuel cells, PMSE (Div. Polym. Mater. Sci. Eng., Am. Chem. Soc.) 85, 520–521 (2001).Google Scholar
  42. 42.
    P. Genova-Dimitrova, B. Baradie, D. Foscallo, C. Poinsignon and J. Y. Sanchez, Ionomeric membranes for proton exchange membrane fuel cell (PEMFC): sulfonated polysulfone associated with phosphatoantimonic acid, J. Membr. Sci. 185, 59–71 (2001).CrossRefGoogle Scholar
  43. 43.
    T. Kobayashi, M. Rikukawa, K. Sanui and N. Ogata, Proton conducting polymers derived from poly(ether-ether ketone) and poly(4-phenoxybenzoyl-,4-phenylene), Solid State Ionics 106, 219 (1998).CrossRefGoogle Scholar
  44. 44.
    C. Bailly, D. J. Williams, F. E. Karasz and W. J. McKnight, The sodium salts of sulfonated poly(aryl ether-ether ketone) (PEEK): preparation and characterization, Polymer 28, 1009 (1987).CrossRefGoogle Scholar
  45. 45.
    Y. M. Kim, S. H. Choi, H. C. Lee, M. Z. Hong, K. Kim and H.-I. Lee, Organic-inorganic composite membranes as addition of SiO2 for high temperature-operation in polymer electrolyte membrane fuel cells (PEMFC)s, Electrochim. Acta 49, 4787–4796 (2004).CrossRefGoogle Scholar
  46. 46.
    D. J. Jones and J. Rozière, Recent advances in the functionalisation of polybenzimidazole and polyetherketone for fuel cell applications, J. Membr. Sci. 185, 41–58 (2001).CrossRefGoogle Scholar
  47. 47.
    D. Hoel and E. Grunwald, High protonic conduction of polybenzimidazole films, J. Phys. Chem. 81, 2135–2136 (1977).CrossRefGoogle Scholar
  48. 48.
    J.-T. Wang, R. F. Savinell, J. Wainright, M. Litt and H. Yu, A H2/O2 fuel cell using acid doped polybenzimidazole as polymer electrolyte, Electrochim. Acta 41, 193–197 (1996).CrossRefGoogle Scholar
  49. 49.
    J. S. Wainright, J.-T. Wang, D. Weng, R. F. Savinell and M. Litt, Acid-doped polybenzimidazoles: a new polymer electrolyte, J. Electrochem. Soc. 142, L121–L123 (1995).CrossRefGoogle Scholar
  50. 50.
    Y.-L. Ma, J. S. Wainright, M. H. Litt and R. F. Savinell, Conductivity of PBI membranes for high-temperature polymer electrolyte fuel cells, J. Electrochem. Soc. 151, A8–A16 (2004).CrossRefGoogle Scholar
  51. 51.
    Q. Li, R. He, J. O. Jensen and N. J. Bherrum, PBI based polymer membrane for high tem fuel cells-preparation, characterization and fuel cell demonstration, Fuel Cells 4, 147–159 (2004).CrossRefGoogle Scholar
  52. 52.
    P. Staiti, M. Minutoli and S. Hocevar, Membranes based on phosphotungstic acid and polybenzimidazole for fuel cell application, J. Power Sources 90, 231–235 (2000).CrossRefGoogle Scholar
  53. 53.
    A. Clearfield, Structural concepts in inorganic proton conductors, Solid State Ionics 46, 35–43 (1991).CrossRefGoogle Scholar
  54. 54.
    L. Xiao, H. Zhang, T. Jana, E. Scanlon, R. Chen, E.-W. Choe, L. S. Ramanathan, S. Yu and B. C. Benicewicz, Synthesis and characterization of pyridine-based polybenzimidazole for high temperature polymer electrolyte membrane fuel cell application, Fuel Cell 5, 287–295 (2005).CrossRefGoogle Scholar
  55. 55.
    J. A. Asensio and P. Gomez-Romero, Recent developments on proton conducting poly(2,5-benzimidazole) (ABPBI) membranes for high temperature polymer electrolyte membrane fuel cells, Fuel Cells 5, 336–343 (2005).CrossRefGoogle Scholar
  56. 56.
    I. Honma, H. Nakajima, O. Nishikawa, T. Sugimoto and S. Nomur, Organic/inorganic nano-composites for high temperature proton conducting polymer electrolytes, Solid State Ionics 162–163, 237–245 (2003).CrossRefGoogle Scholar
  57. 57.
    I. Honma, H. Nakajima and S. Nomura, High temperature proton conducting hybrid polymer electrolyte membranes, Solid State Ionics 154–155, 707–712 (2002).CrossRefGoogle Scholar
  58. 58.
    I. Honma, S. Nomura and H. Nakajim, Protonic conducting organic/inorganic nanocomposites for polymer electrolyte membrane, J. Membr. Sci. 185, 83–94 (2001).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Xiuling Zhu
  • Yuxiu Liu
  • Lei Zhu

There are no affiliations available

Personalised recommendations