DOI QR코드

DOI QR Code

Preparation and Characterization of Nafion Composite Membranes Containing 1-ethyl-3-methylimidazolium Tetracyanoborate

  • Shin, Mun-Sik (Department of Environmental Engineering, College of Engineering, Sangmyung University) ;
  • Park, Jin-Soo (Department of Environmental Engineering, College of Engineering, Sangmyung University)
  • Received : 2012.01.13
  • Accepted : 2012.01.27
  • Published : 2012.02.28

Abstract

The composite membranes using Nafion as matrix and 1-ethyl-3-methylimidazolium tetracyanoborate (EMITCB) as ion-conducting medium in replacement of water were prepared and characterized. The amount of EMITCB in Nafion varied from 30 to 50wt%. The composite membranes are characterized by ion conductivity, thermogravitational analyses (TGA) and small-angle X-ray scattering (SAXS). The composite membranes containing EMITCB of 40wt% showed the maximum ionic conductivity which was ~0.0146 S $cm^{-1}$ at 423.15 K. It is inferred that the decrease in ionic conductivity of all the composite membranes might be due to the decomposition of a tetracyanoboric acid formed in the composite membranes. The results of SAXS indicated that the ionic clusters to conduct proton in the composite membranes were successfully formed. In accordance with the results of ionic conductivity as a function of a reciprocal temperature, SAXS showed a proportional decrease in scattering maximum $q_{max}$ as the amount of EMITCB increases in the composite membranes, which results in the increase in ionomer cluster size. The TGA showed no significant decomposition of the ionic liquid as well as the composite membranes in the range of operating temperature ($120-150^{\circ}C$) of high temperature proton exchange membrane fuel cells (HTPEMFC). As a result, EMITCB is able to play an important role in transferring proton in the composite membranes at elevated temperatures with no external humidification for proton exchange membrane fuel cells.

Acknowledgement

Supported by : Sangmyung University

References

  1. E. Cho, J.-S. Park, S. S. Sekhon, G.-G. Park, T.-H. Yang, W.-Y. Lee, C.-S. Kim, and S.-B. Park, 'A Study on Proton Conductivity of Composite Membranes with Various Ionic Liquids for High-Temperature Anhydrous Fuel Cells' J. Electrochem. Soc., 156, B197 (2009). https://doi.org/10.1149/1.3031406
  2. S. S. Sekhon, J.-S. Park, J.-S. Baek, S.-D. Yim, T.-H. Yang, and C.-S. Kim, 'Small-angle X-ray scattering study of water free fuel cell membranes containing ionic liquids' Chem. Mater., 22, 803 (2010). https://doi.org/10.1021/cm901465p
  3. S. S. Sekhon, J.-S. Park, E. Cho. Y.-G. Yoon, C.-S. Kim, and W.-Y. Lee, 'Morphology studies of high temperature proton conducting membranes containing hydrophilic/hydrophobic ionic liquids' Macromolecules, 42, 2054 (2009). https://doi.org/10.1021/ma8027112
  4. S. S. Sekhon, J.-S. Park, and Y.-W Choi, 'A SAXS study on nanostructure evolution in water free membranes containing ionic liquid: from dry membrane to saturation' Phys. Chem. Chem. Phys., 12, 13763 (2010). https://doi.org/10.1039/c0cp00966k
  5. J.-S. Baek, J.-S Park, S. S. Sekhon, T.-H. Yang, Y.-G. Shul, and J.-H. Choi, 'Preparation and characterization of non-aqueous proton-conducting membranes with the low content of ionic liquids' Fuel Cells, 10, 762 (2010). https://doi.org/10.1002/fuce.200900176
  6. J.-S. Park, M.-S. Shin, S. S. Sekhon, Y.-W. Choi, and T.-H. Yang, 'Effect of annealing of Nafion recast membranes containing ionic liquids' J. Kor. Electrochem. Soc., 14, 9 (2011). https://doi.org/10.5229/JKES.2011.14.1.009
  7. Q. Li, R. He, J. O. Jensen, and N. J. 'Bjerrum, Approaches and Recent Development of Polymer Electrolyte Membranes for Fuel Cells Operating above $100{^{\circ}C}$' J. Chem. Mater., 15, 4896-4915 (2003). https://doi.org/10.1021/cm0310519
  8. J. Roziere, and D. J. Jones, 'Non-fluorinated polymer materials for proton exchange membrane fuel cells' Annu. Rev. Mater. Res., 33, 503 (2003). https://doi.org/10.1146/annurev.matsci.33.022702.154657
  9. Y. Woo, S. Y. Oh, Y. S. Kang, and B. Jung, 'Synthesis and characterization of sulfonated polyimide membranes for direct methanol fuel cell' J. Membr. Sci., 220, 31 (2003). https://doi.org/10.1016/S0376-7388(03)00185-6
  10. T. D. Gierke, G. E. Munn, and F. C. Wilson, 'The morphology in nafion perfluorinated membrane products, as determined by wide-and small-angle x-ray studies' J. Polym. Sci.: Polym. Phys. Ed., 19, 1687 (1981). https://doi.org/10.1002/pol.1981.180191103
  11. B. Dreyfus, G. Gebel, G. P. Aldebert, M. Pineri, and M. Escoubes, 'Distribution of the < micelles > in hydrated perfluorinated ionomer membranes from SANS experiments' J. Phys. France, 51, 1341 (1990). https://doi.org/10.1051/jphys:0199000510120134100
  12. G. Gebel and J. Lambard, 'Small-Angle Scattering Study of Water-Swollen Perfluorinated Ionomer Membranes' Macromolecules, 30, 7914 (1997). https://doi.org/10.1021/ma970801v
  13. S. Kumar and M. Pineri, 'Interpretation of small-angle xray and neutron scattering data for perfluorosulfonated ionomer membranes' J. Polym. Sci. B, 24, 1767 (1986). https://doi.org/10.1002/polb.1986.090240812
  14. A. S. Ioselevich, A. A. Kornyshev, and J. H. G. Steinke, 'Fine Morphology of Proton-Conducting Ionomers' J. Phys. Chem. B, 108, 11953 (2004). https://doi.org/10.1021/jp049687q
  15. Product catalogue "In search of tomorrow's innovations?: Ionic liquid for electrochemical applications" from Merck.

Cited by

  1. Synthesis and Characterization of 5-Cyanotetrazolide-Based Ionic Liquids vol.21, pp.6, 2015, https://doi.org/10.1002/chem.201405264
  2. Hydrocarbon Composite Membranes with Improved Oxidative Stability for PEMFC vol.17, pp.1, 2014, https://doi.org/10.5229/JKES.2014.17.1.44
  3. Hydrocarbon-Organic Composite Membranes for Improved Oxidative Stability for PEMFC Applications vol.19, pp.2, 2016, https://doi.org/10.5229/JKES.2016.19.2.45
  4. Influence of cationic structures on oxygen reduction reaction at Pt electrode in fluorohydrogenate ionic liquids vol.266, 2014, https://doi.org/10.1016/j.jpowsour.2014.05.019