Cross-linked SPAES/SiO2 Hybrid Membranes for Polymer Electrolyte Membrane Fuel Cells

  • Shaoguang Feng, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China
  • Prof Yuming Shang, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China
  • Dr Yan Chen, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China
  • Prof Xiaofeng Xie, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084
  • Prof Jingming Xu, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084

    • The proton exchange membrane is one of the key components of Polymer Electrolyte Membrane Fuel Cells (PEMFCs).
    Much research efforts are devoted to the development of new electrolytes. One interesting alternative is the hybrid organic/inorganic membranes which have the potential to provide unique combinations of organic and inorganic properties. The organic component may provide mechanical strength and proton conductivity, whereas the inorganic phase can reduce methanol permeation and improve thermal and chemical stabilities at the same time.
    Furthermore, in order to control the dosage and dispersion of the inorganic component and make it more compatible with the organic phase, a covalent cross-linked could be designed and formed between the two phases. The properties of such covalent hybrids can be modulated by modifying the ratio between organic and inorganic groups and the nature of the chemical components.
    Organic/inorganic hybrids were synthesized by reaction of covalently cross-linked sulfonated poly (arylene ether sulfone)s(SPAES, Fig.1) with tetraethylorthosilicate(TEOS) and vinyltriethoxysilane(VTOS), followed by hydrolysis. Further amounts of inorganic component were added by sol-gel reaction with TEOS and VTOS to modulate mechanical properties and electrical performance.
    Fig. 2 shows the cross-sectional images of membrane. From the images, it can be observed that the hybrid membrane is dense, and with no obvious phase separation, which suggests that inorganic component and polymer base form cross-linked structure.
    The comprehensive properties of the virgin and the cross-linked membranes were compared accordingly. The results showed that the cross-linked membranes revealed the better mechanical, oxidative and dimensional stabilities together with high proton conductivity.