OPEN ACCESS
Composite membranes have been prepared by impregnation of PFSI(perfluorosulphonic acid ionomer) solution (Nafion®) into the expanded polytetrafluoroethylene (EPTFE) matrix. The matrix was modified by Na/Naphthalene treatment and with phosphotungstic acid (PTA). The matrix modifications helped in reducing the contact angle thereby improving the impregnation process by reducing the hydrophobicity of the matrix. The fuel cell made with these composite membranes showed that the performance of PTA modified matrix is comparable to that of Na/ naphthalene modified matrix. Further the performances of matrix modified membranes were higher than that of the as received matrix-composites. PTA treatment offers a simple method of matrix modification to achieve high performance.
polymer electrolyte membrane fuel cells, Composite ionomers, expanded PTFE, Phosphotungstic acid, surface modification
The authors would like to thank Dr.G.Sundararajan, Director, ARCI, Hyderabad and Dr. K S Dhathathreyan, Associate Director, CFCT for supporting this work and Department of Science and Technology, Government of India for financial support. The authors would like to thank Dr.Y.S.Rao, Dr. R.Subasri and Dr. G. Ravichandra of ARCI for their help in characterizing the membranes.
[1] R.S. Yeo, H.L. Yeager, Mod. Aspects Electrochem, B.E. Conway, R.E. White, J. O’M Bockris Eds., Plenum Press, 16, 437 (1985).
[2] T.L. Yu, H.S. Lin, K.S. Shen, L.N. Huang, Y.C. Chang, G.B. Jung, J.C. Huang, J. Polymer Reasearch, 11, 217 (2004).
[3] W. Liu, K. Ruth, G. Rusch, J. New Mat. Electrochem. Systems, 4, 227 (2001).
[4] J. Shim, H.Y. Ha, S.A. Hong, I.H. Oh, J. Power Sour., 109, 412 (2002).
[5] C. Liu, C.R. Martin, J. Electrochem. Soc., 137, 510 (1990).
[6] C. Liu, C.R. Martin, J. Electrochem Soc., 137, 3114 (1990).
[7] K. Ramya, G. Velayutham, C.K. Subramaniam, N. Rajalakshmi, K.S. Dhathathreyan, J. Power Sources, 160, 10 (2006).
[8] H.L. Lin, T.L. Yu, K.S. Shen, L.N. Huang, J. Memb. Sci., 237, 1 (2004).
[9] H. Tang, M. Pan, S.P. Jiang, X. Wang, Y. Ruan, Electrochim. Acta, 52, 5304 (2007).
[10] Z. Jie, T. Haolin, P. Mu, J. Memb. Sci., 312, 41 (2008).
[11] G. Pourcelly, C. Gavach in P. Columban(ed.), Proton conductors- solids, membranes and gel materials and devices, Cambridge University press, New york, 1992, p 294.
[12] B. Tazi, O. Savadago, Electrochemica Acta, 45, 4329 (2000).
[13] Y.S. Kim, F. Wang, M. Hickner, T.A. Zawodzinski, J.E. Mcgrath, J. Memb Sci., 212, 263 (2003).
[14] V. Ramani, H.R. Kunz and J.M. Fenton, J. Memb. Sci., 266, 110 (2005).
[15] S. Malhotra and R. Dutta, J. Electrochem Soc., 144, L23 (1997).
[16] A.G. Kannan, N.R. Chaudhary, N.H. Dutta, J. Memb. Sci., 333, 50 (2009).