Proton-exchange membrane fuel cell electrocatalysis

Lefebvre, M. Qi, Z. Pickup, P. G. (1999). Electronically conductive proton-exchange polymers as catalyst supports for proton-exchange membrane fuel cells electrocatalysis of oxygen reduction, hydrogen oxidation, and methanol oxidation. J. Electrochem. Soc., 146, 2054-2058. 

Significant (and even spectacular) results were contributed by the group of Norskov to the field of electrocatalysis [102-105]. Theoretical calculations led to the design of novel nanoparticulate anode catalysts for proton exchange membrane fuel cells (PEMFC) which are composed of trimetallic systems where which PtRu is alloyed with a third, non-noble metal such as Co, Ni, or W. Remarkably, the activity trends observed experimentally when using Pt-, PtRu-, PtRuNi-, and PtRuCo electrocatalysts corresponded exactly with the theoretical predictions (cf. Figure 5(a) and (b)) [102]. 

Muketjee S, Srinivasan S. 1993. Enhanced electrocatalysis of oxygen reduction on platinum alloys in proton exchange membrane fuel cells. J Electroanal Chem 357 201-224. 

Mukeijee S, Srinivasan S. 1993. Enhanced electrocatalysis of oxygen reduction on platinum alloys in proton exchange membrane fuel cells. J Electroanal Chem 357 201-224. Mukeijee S, Srinivasan S, Soriaga M, McBreen J. 1995. Role of structural and electronic properties of Pt and Pt alloys on electrocatalysis of oxygen reduction. J Electrochem Soc 142 1409-1422. 

DMFCs and direct ethanol fuel cells (DEFCs) are based on the proton exchange membrane fuel cell (PEM FC), where hydrogen is replaced by the alcohol, so that both the principles of the PEMFC and the direct alcohol fuel cell (DAFC), in which the alcohol reacts directly at the fuel cell anode without any reforming process, will be discussed in this chapter. Then, because of the low operating temperatures of these fuel cells working in an acidic environment (due to the protonic membrane), the activation of the alcohol oxidation by convenient catalysts (usually containing platinum) is still a severe problem, which will be discussed in the context of electrocatalysis. One way to overcome this problem is to use an alkaline membrane (conducting, e.g., by the hydroxyl anion, OH ), in which medium the kinetics of the electrochemical reactions involved are faster than in an acidic medium, and then to develop the solid alkaline membrane fuel cell (SAMFC). 

Carbon supported Pt and Pt-alloy electrocatalysts form the cornerstone of the current state-of-the-art electrocatalysts for medium and low temperature fuel cells such as phosphoric and proton exchange membrane fuel cells (PEMECs). Electrocatalysis on these nanophase clusters are very different from bulk materials due to unique short-range atomic order and the electronic environment of these cluster interfaces. Studies of these fundamental properties, especially in the context of alloy formation and particle size are, therefore, of great interest. This chapter provides an overview of the structure and electronic nature of these supported... 

The held to which the specific features of CNTs and CNFs could bring the most significant advancements is perhaps that of fuel cell electrocatalysis [125,187]. The main uses of CNTs or CNFs as catalyst support for anode or cathode catalysis in direct methanol fuel cells (DMFCs) or proton-exchange membrane fuel cells (PEMFCs) are covered in Chapter 12. In this section we summarize the main advantages linked to the use of nanotubes or nauofibers for these applications. 

R.N., Gu, W., Hu, Y., Wagner, F.T., and Yu, P.T. (2010) Electrocatalysis and Catalyst D adation Challenges in Proton Exchange Membrane Fuel Cells, Wiley-VCH Verlag GmbH, Weinheim. 

Chemical reactions are temperature sensitive, and indeed, chemical rate constants and reactions mechanism are expected to vary considerably with temperature. Most investigations on the electrocatalysis of the ORR are usually performed at ambient conditions, which do not necessarily represent the behavior of the materials and the reaction at the conditions of practical interest. For example, in proton exchange membrane fuel cells, the temperature of operation is between 80 and 100 °C. Significant discrepancy in behavior may arise if reactions and materials are tested at ambient conditions and their behavior at high temperatures is merely deduced firom extrapolation. Schafer et al. introduced variable temperature SECM, with an operational range of 0-100 °C, by integrating a temperature control unit (Peltier element) into an SECM setup, as shown in the schematic of Fig. 23 [66]. At the heart of the temperature control unit is the Peltier element, which is housed in a stainless steel block. 

Gu W, Baker DR, Liu Y, Gasteiger HA (2009) Proton exchange membrane fuel cell (PEMFC) down-the-charmel performance model. In Vielstich W, Gasteiger HA, Yokokawa H (eds) Handbook of fuel cells - advances in electrocatalysis, materials, diagnostics, and durability, vol 5. Wiley, Chichester, pp 631-657... 

Urian RC, Gulla AF, Mukeijee S. Electrocatalysis of reformate toleranee in proton exchange membranes fuel cells Part I. J Electroanal Chem 2003 554—555 307-24. 

R.C. Urian, A.F. Gulla, S. Mukerjee, 2003. Electrocatalysis of reformate tolerance in proton exchange membrane fuel cells Part 1. Journal of Electroanalytical Chemistry, 554,555 307-324. 

GB/T 20042.4-2009 Proton exchange membrane fuel cell—Part 4 Test method for electrocatalysis (China)... 

Urian, R. C., Gulla, A. R, and Mukerjee, S. (2003). Electrocatalysis of reformate tolerance in proton exchange membranes fuel cells Part 1.1. Electroanal. Chem. 554-555 307-324 Uribe, F. A., Valerio, J. A., Garzon, F. H., and Zawodzinski, T. A. (2004). PEMFC reconfigured anodes for enhancing CO tolerance with air bleed. Electrochem. Solid-State Letts. 7(10) A376-A379... 

Kim DS, Guiver MD, Kim YS (2009) Proton exchange membranes for direct methanol fuel cells. In Liu A, Zhang J (eds) Electrocatalysis of direct methanol fuel cells. Wiley-VCH, Weinheim, pp 379 16, Chap. 10... 

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