Get access

Temperature- and Humidity-Controlled SAXS Analysis of Proton-Conductive Ionomer Membranes for Fuel Cells

Authors

  • Takashi Mochizuki,

    1. Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4 Takeda, Kofu, Yamanashi 400-8510 (Japan)
    Search for more papers by this author
  • Prof. Dr. Katsuyoshi Kakinuma,

    1. Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)
    Search for more papers by this author
  • Prof. Dr. Makoto Uchida,

    1. Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)
    Search for more papers by this author
  • Prof. Dr. Shigehito Deki,

    1. Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)
    Search for more papers by this author
  • Prof. Dr. Masahiro Watanabe,

    Corresponding author
    1. Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)
    • Masahiro Watanabe, Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)

      Kenji Miyatake, Clean Energy Research Center, University of Yamanashi, 4 Takeda, Kofu, Yamanashi 400-8510 (Japan)

    Search for more papers by this author
  • Prof. Dr. Kenji Miyatake

    Corresponding author
    1. Clean Energy Research Center, University of Yamanashi, 4 Takeda, Kofu, Yamanashi 400-8510 (Japan)
    • Masahiro Watanabe, Fuel Cell Nanomaterials Center, University of Yamanashi, 6-43 Miyamae-cho, Kofu, Yamanashi 400-0021 (Japan)

      Kenji Miyatake, Clean Energy Research Center, University of Yamanashi, 4 Takeda, Kofu, Yamanashi 400-8510 (Japan)

    Search for more papers by this author

Abstract

We report herein temperature- and humidity-controlled small-angle X-ray scattering (SAXS) analyses of proton-conductive ionomer membranes. The morphological changes of perfluorosulfonic acid polymers (Nafion and Aquivion) and sulfonated aromatic block copolymers (SPE-bl-1 and SPK-bl-1) were investigated and compared under conditions relevant to fuel cell operation. For the perfluorinated ionomer membranes, water molecules were preferentially incorporated into ionic clusters, resulting in phase separation and formation of ion channels. In contrast, for the aromatic ionomer membranes, wetting led to randomization of the ionic clusters. The results describe the differences in the proton-conducting behavior between the fluorinated and nonfluorinated ionomer membranes, and their dependence on the humidity.

Ancillary