Reductive oxygen activation

We have already referred to the Mo/Ru/S Chevrel phases and related catalysts which have long been under investigation for their oxygen reduction properties. Reeve et al. [19] evaluated the methanol tolerance, along with oxygen reduction activity, of a range of transition metal sulfide electrocatalysts, in a liquid-feed solid-polymer-electrolyte DMFC. The catalysts were prepared in high surface area by direct synthesis onto various surface-functionalized carbon blacks. The intrinsic... 

Stamenkovic V, Fowler B, Mun BS, Wang G, Ross PN, Lucas CA, Markovic NM. 2007a. Improved oxygen reduction activity on Pt3Ni(lll) via increased surface site availabihty. Science 315 493-497. 

Higuchi E, Uchida H, Watanahe M. 2005. Effect of loading level in platinum-dispersed carbon black electrocatalysts on oxygen reduction activity evaluated by rotating disk electrode. J Electroanal Chem 583 69-76. 

Wakabayashi N, Takeichi M, Itagaki M, Uchida M, Watanabe M. 2(X)5a. Temperature-dependence of oxygen reduction activity at a platinum electrode in an acidic electrolyte solution investigated with a channel flow double electrode. J Electroanal Chem 574 339-346. 

Yano H, Higuchi E, Uchida H, Watanabe M. 2006a. Temperature dependence of oxygen reduction activity at Nafion-coated bulk Pt and Pt/carbon black catalysts. J Phys Chem B 110 16544-16549. 

Yano H, Kataoka M, Yamashita H, Uchida H, Watanabe M. 2007. Oxygen reduction activity of carbon supported Pt-M (M = V, Ni, Cr, Co and Fe) alloys prepared by nanocapsule method. Langmuir 23 6438-6445. 

Hwang JT, Chung JS. 1993. The morphological and surface properties and their relationship with oxygen reduction activity for platinum-iron electrocatalysts. Electrochim Acta 38 2715-2723. 

Baker WS, Pietron JJ, Teliska ME, et al. 2006. Enhanced oxygen reduction activity in acid by tin-oxide supported Au nanoparticle catalysts. J Electrochem Soc 153 A1702-A1707. Blizanac BB, Lucas CA, Gallagher ME, et al. 2004a. Anion adsorption, CO oxidation, and oxygen reduction reaction on a Au(lOO) surface The pH effect. J Phys Chem B 108 625-634. 

T. Ito, K. Kato, S. Kamitomai, M. Kamiya, "Organization of Platinum Loading Amount of Carbon-Supported Alloy Cathode for Advanced Phosphoric Acid Fuel Cell," in Fuel Cell Seminar Abstracts, 1990 Fuel Cell Seminar, Phoenix, AZ, November 25-28, 1990. J.S. Buchanan, G.A. Hards, L. Keck, R.J. Potter, "Investigation into the Superior Oxygen Reduction Activity of Platinum Alloy Phosphoric Acid Fuel Cell Catalysts," in Fuel Cell Seminar Abstracts, Tucson, AZ, November 29-December 2, 1992. 

Trends in calculated oxygen reduction activity plotted as a function of the oxygen binding energy. (Reprinted with permission from ]oumal of Physical Chemistry B, 108, 17886 (2004). Copyright 2004 American Chemical Society.)... 

Ruthenium/carbon catalysts have also been promoted by the addition of Fe. Bron et al. reported the addition of Fe to a preformed Ru/C catalyst via adsorption of Fe complexes, followed by heat treatment. They found an increase in oxygen reduction activity of three to five times over unmodified Ru/C. It was suggested that the surfaces of Ru particles were covered with FeN,Cy sites. As discussed previously, the Pd alloys have shown significant MeOH tolerance toward oxygen reduction and appear to have activities closest to that of Ft. 

Ternary and more complex alloys are now the subjects of investigations that seek further improvements in oxygen reduction activity. Struc-... 

Figure 6.18. Trends in oxygen reduction activity plotted as function of the oxygen binding energy (adapted from Ref. [117]). Solid line associative mechanism arrows rate determining processes dashed line associative mechanism.

They calculated energies of different intermediate states. The results demonstrated that there was a correlation between oxygen reduction activity and the binding ability of O and OH. They further... 

Lefevre M, Proietti E, Jaouen F, Dodelet J-P. Iron-based catalysts with improved oxygen reduction activity in polymer electrolyte fuel cells. Science. 2009 324 71-4. 

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