Polymer electrolyte fuel cells shift

One particular application for which supported Au catalysts may find a niche market is in fuel cells [4, 50] and in particular in polymer electrolyte fuel cells (PEFC), which are used in residential electric power and electric vehicles and operate at about 353-473 K. Polymer electrolyte fuel cells are usually operated by hydrogen produced from methane or methanol by steam reforming followed by water-gas shift reaction. Residual CO (about 1 vol.%) in the reformer output after the shift reaction poisons the Pt anode at a relatively low PEFC operating temperature. To solve this problem, the anode of the fuel cell should be improved to become more CO tolerant (Pt-Ru alloying) and secondly catalytic systems should be developed that can remove even trace amounts of CO from H2 in the presence of excess C02 and water. 

D. J. Myers, J. F. Krebs, J. D. Carter, R. Kumar, and M. Krumpelt, "Metal/Ceria Water-Gas Shift Catalysts for Automotive Polymer Electrolyte Fuel Cell Systems," Presentation, Abstract, and Presentation Reeord, American Institute of Chemieal Engineers, 2002 Spring Meeting, Fuel Proeessing Session III, New Orleans, LA, Mareh... 

Bosco, M., Hajbolouri, F., Truong, T.B., De Boni, E., Vogel, E. and Scherer, G.G. (2006) Link-up of a bench-scale shift-less gasoline fuel processor to a polymer electrolyte fuel cell. J. Power Sources, 159, 1034-1041. 

The water-gas shift (WGS) reaction is the exothermic conversion of carhon monoxide and water to hydrogen and carbon dioxide according to Scheme 16.1 [1, 2], The reaction is of industrial importance for purification when traces of carbon monoxide have to be removed from gaseous feed, such as in the Haber-Bosch process for ammonia production or in modem polymer electrolyte membrane (PEM) fuel cells [3]. 

HjSO, but the magnitude of the current density was not affected largely up to a concentration of lOmmol dm . With 2-propanol, the current due to the alcohol oxidation was superimposed on the ORR current, and the potential shifted by approximately 0.5 V at 0.1 mol dm . Both 2-propanol and acetone are MEA components because 2-propanol is added to the catalyst ink, and acetone is produced by oxidation of 2-propanol on the platinum cathode. The effects are, however, not serious because their concentration is less than lOmmol dm . Methanol is used as a fuel in direct methanol fuel cells, and crossover through the polymer electrolyte membrane is known to cause a degradation of the ORR at the cathode, when the concentration of the fuel is as high as 5 mol dm . 

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