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Essay / Proton exchange membrane fuel cell (PEMFC) - 749
An H2/O2 proton exchange membrane fuel cell (PEMFC) is a clean, sustainable energy source suitable for operating small electronic devices [1]. Among the many problems that still exist for PEMFC, slow reactions at the cathode electrode and poor mass transport of protons and electrons decrease fuel cell performance by increasing the activation overvoltage, or loss. activation [2]. This problem can, however, be solved by increasing the operating temperature of the fuel cell [3], but only up to a certain temperature before deformation or degradation of the polymer components occurs. Thus, reducing the activation overvoltage for fuel cell operation at low temperatures is still necessary when PEMFC components are made of polymer. For electrode layers consisting of a catalyst supported on carbon black which tends to agglomerate, previous studies have shown a significant decrease in activation overvoltage by forming the three-phase boundary (i.e. i.e. ionomer, catalyst and gas) in the primary pores, or spaces between carbon black particles in an agglomerate, and secondary pores, or spaces between agglomerates, which can accelerate redox reactions in the electrodes, increase the use of the catalyst and the performance of the fuel cell [4-6]. It has been shown that ionomeric molecules that can be found in the primary pores of carbon black particles (< 40 nm in diameter) must have low molecular weight [7] or can be formed by polymerization of monomers present in the pores primary [8]. On the other hand, ionomeric molecules with molecular weights of the order of several hundred thousand grams per mole (for example Nafion) cannot penetrate the primary pores and only remain in the secondary pores..... .. middle of paper..... .Systems Explained, John Wiley & Sons, England, 2003.[4] T. Nakajima, T. Tamaki, H. Ohashi, T. Yamaguchi, J. Electrochem. Soc. 160 (2013) F129−F134.[5] M. Uchida, Y. Fukuoka, Y. Sugawara, N. Eda, A. Ohta, J. Electrochem. Soc. 143 (1996) 2245−2252.[6] H. Mizuhata, S.-i. Nakao, T. Yamaguchi, J. Power Sources 138 (2004) 25−30.[7] W. Phompan, N. Hansupalak, J. Power Sources 196 (2011) 147−152.[8] M. Carmo, T. Roepke, C. Roth, AM dos Santos, JGR Poco, M. Linardi, J. Power Sources 191 (2009) 330−337.[9] M. Watanabe, M. Tomikawa, S. Motoo, Journal of Electroanalytical Chemistry 195 (1985) 81−93.[10] M. Uchida, Y. Aoyama, N. Eda, A. Ohta, J. Electrochem. Soc. 142 (1995) 4143−4149[11] Thanganathana U, Dixon D, Ghatty SL, Bobba R, Int. J. Hydrogen Energy 37 (2012) 17810−17820.[12] J. Parrondo, F. Mijangos, B. Rambabu, J. Energy sources 195 (2010) 3977−3983.