PVA/SSA/HPA Composite Membranes on the Application to Polymer Electrolyte Membrane Fuel Cell

PVA/SSA/HPA 복합막의 고분자전해질 연료전지에의 응용연구

  • Oh Sae-Joong (Department of Chemical Engineering, Sun-Moon University) ;
  • Tongzhai Gao (Department of Chemical Engineering, Sun-Moon University)
  • 오세중 (선문대학교 생명화학공학과) ;
  • Published : 2006.03.01

Abstract

PVA/SSA/HPA composite membranes were prepared by the addition of SSA as a crosslinking agent and HPA such as PWA or SiWA. The water uptake decreased and the IEC increased as the HPA contents increased in PVA/SSA/HPA composite membranes. XRD results showed that HPA distributed well into the composite membranes as the HPA concentration increased, and SiWA dispersed better than PWA in the composite membranes. TGA results showed that PVA/SSA composite membranes were more heat-resistant than PVA due to the crosslinking of PVA, and the heat stability of the composite membranes improved much more as the concentration of HPA increased. The methanol barrier property of PVA/SSA/HPA composite membranes was superior to Nafion, and the methanol permeability of the composite membranes decreased as the concentration of HPA increased.

Polyvinylalcohol (PVA)을 전해질 막으로 이용하여 위하여 가교제로서 sulfosuccinic acid (SSA)와 무기물 첨가제로 phosphotungstic acid (PWA), silicotungstic acid (SiWA) 등의 HPA (heteropolyacid)를 사용하여 PVA/SSA/HPA 복합막을 제조하였다. PVA/SSA/HPA 복합막은 HPA의 농도가 증가함에 따라 함수율은 감소하였으나 IEC값은 증가하는 경향을 나타내었다. PVA/SSA/HPA 복합막의 XRD 분석 결과 HPA의 농도가 증가함에 따라 HPA가 복합막 속으로 잘 분산되는 것을 확인할 수 있었으며 HPA로서 PWA보다 SiWA의 분산성이 우수하였다. TGA 분석결과 PVA/SSA 복합막은 가교 결합으로 인하여 PVA 보다 열안정성이 우수하였으며 복합막의 HPA의 농도가 증가할수록 열안정성이 더욱 증대되는 것을 알 수 있었다. PVA/SSA/HPA 복합막의 메탄올 투과저항은 Nafion보다 현저히 우수하였으며 HPA의 농도가 증가할수록 메탄올의 투과도는 감소하였다.

Keywords

References

  1. J. Larminie and A. Dicks, 'Fuel cell systems Explained', 2nd Ed., Wiley (2003)
  2. V. Ramani, H. R. Kunz, and J. M. Fenton, 'Investigation of Nafion/HPA composite membranes for high temperature/low relative humidity PEMFC operation', J. Membr. Sci., 232, 31 (2004) https://doi.org/10.1016/j.memsci.2003.11.016
  3. J. Lin, H. Wang, S. Cheng, and K. Chan, 'Nafionpolyfurfuryl alcohol nanocomposite membranes for direct methanol fuel cells', J. Membr. Sci., 246, 95 (2005) https://doi.org/10.1016/j.memsci.2004.08.016
  4. Z. Q. Ma, P. Cheng, and T. S. Zhao, 'A palladium-alloy deposited nafion membrane for direct methanol fuel cells', J. Membr. Sci., 215, 327 (2003) https://doi.org/10.1016/S0376-7388(03)00026-7
  5. H. B. Park, H. S. Shin, Y. M. Lee, and J. W. Rhim, 'Annealing effect of sulfonated polysulfone ionomer membranes on proton conducivity and methanol transport', J. Membr. Sci., 247, 103 (2005) https://doi.org/10.1016/j.memsci.2004.09.023
  6. J. Kerres, C. M. Tang, and C. Graf, 'Improvement of properties of polyetherketone ionomer membranes by blending and crosslinking', Ind. Eng. Chem. Res., 43, 4571 (2004) https://doi.org/10.1021/ie030762d
  7. M. L. Ponce, L. Prado, B. Ruffmann, K. Richau, R. Mohr, and S. P. Nunes, 'Reduction of Methanol permeability in polyetherketone-heteropolyacid membranes', J. Membr. Sci., 217, 5 (2003) https://doi.org/10.1016/S0376-7388(02)00309-5
  8. C. W. Lin, R. Thangamuthu, and C. J. Yang, 'Proton-conducting membranes with high selectivity from phosphotungstic acid-doped polyvinylalcohol for DMFC applications', J. Membr. Sci., 253, 23 (2005) https://doi.org/10.1016/j.memsci.2004.12.021
  9. J. W. Lim, H. B. Park, C. S. Lee, J. H. Jun, D. S. Kim, and Y. M. Lee, 'Crosslinked poly(vinyl alcohol) membranes containing sulfonic acid group: proton and methanol transport through membranes', J. Membr. Sci., 238, 143 (2004) https://doi.org/10.1016/j.memsci.2004.03.030
  10. S. Y. Lee and Y. M. Lee, 'Polyvinylalcohol membranes containing sulfonic acid groups for direct methanol fuel cell application', Membr. J. 14, 3, 240 (2004)
  11. J. Qiao, T. Hamaya, and T. Okada, 'New highly proton-conducting membrane poly(vinylpyrrolidone) modified poly(vinylalcohol)/2-acrylamino-2-methyl-propanesulfonic acid(PVA-PAMPS) for low temperature direct methanol fuel cells (DMFCs)', Polymer, 46, 10809 (2005) https://doi.org/10.1016/j.polymer.2005.09.007