Oxygen reduction reaction kinetics

Antoine O, Bultel Y, Durand R. 2001. Oxygen reduction reaction kinetics and mechanism on platinum nanoparticles inside Nafion . J Electroanal Chem 499 85-94. 

Figure 5.3. Electrode potential effects on ORR impedance spectra using GDE AC frequency range 6 x 104 to 6 x 10 3 Hz. Electrode potentials (versus SCE) ( ) 0.54 V (+) 0.49 V (x) 0.44 V (o) 0.39 V [6], (Reprinted from Journal of Electroanalytical Chemistry, 499, Antoine O, Bultel Y, Durand R. Oxygen reduction reaction kinetics and mechanism on platinum nanoparticles inside Nafion , 85-94, 2001, with permission from Elsevier.)...

O. Antoine, Y. Bultel, and R. Durand, "Oxygen Reduction Reaction Kinetics and Mechanism on Platinum Nanoparticles Inside Nafion," Journal of Electro-analytical Chemistry, 499 (2001) 85-94. 

However, for technical use of AFC, the long-term behavior of AFC components is important, especially that of the electrodes. Nickel can be used for the hydrogen oxidation reaction (catalyst in the anode) and on the cathode silver can be used as catalyst (see next section), no expensive noble metal (platinum) is necessary, because the oxygen reduction reaction kinetics are more rapid in alkaline electrolytes than in acids and the alkaline electrochanical environment in AFC is less corrosive compared to acid fuel cell conditions. Both catalysts and electrolyte represents a big cost advantage. The advantages of AFC are not restricted only to the cheaper components, as shown by Giilzow [1996]. 

Ilevbare GO, Scully JR. Oxygen reduction reaction kinetics on chromate conversion coated Al-Cu, Al-Cu-Mg, and Al-Cu-Mn-Fe intermetallic compounds. J Electrochem... 

Garsany, Y, Baturina, O. A., and Swider-Lyons, K. E. 2009a. Oxygen reduction reaction kinetics of SOj-contaminated Pt3Co and Pt/Vulcan carbon electrocatalysts. Journal of the Electrochemical Society 156 B848-B855. 

Chen, C.-H. Meadows, K. E. Cuharuc, A. Lai, S. C. Unwin, P. R., High resolution mapping of oxygen reduction reaction kinetics at polycrystalline platinum electrodes. Physical Chemistry Chemical Physics 2014,16, 18545-18552. 

The mechanism of the oxygen reduction reaction is by no means as fully understood as the h.e.r., and a major experimental difficulty is that in acid solutions (pH = 0) E02/H20 = 1 23, which means that oxygen will start to be reduced at potentials at which most metals anodically dissolve. For this reason accurate data on kinetics is available only for the platinum metals. In the case of an iridium electrode at which oxygen reduction is relatively rapid, a number of reaction sequences have been proposed, of which the most acceptable appear to be the following ... 

In this section, we summarize the kinetic behavior of the oxygen reduction reaction (ORR), mainly on platinum electrodes since this metal is the most active electrocatalyst for this reaction in an acidic medium. The discussion will, however, be restricted to the characteristics of this reaction in DMFCs because of the possible presence in the cathode compartment of methanol, which can cross over the proton exchange membrane. 

Parthasarathy A, Srinivasan S, Appleby AJ, et al. 1992b. Pressure dependence of the oxygen reduction reaction at the platinum microelectrode/Nafion interface Electrode kinetics and mass transport. J Electrochem Soc 139 2856-2862. 

Stamenkovic V, Schmidt TJ, Ross PN, Markovic NM. 2003. Surface segregation effects in electrocatalysis Kinetics of oxygen reduction reaction on polycrystalline PtsNi alloy surfaces. J Electroanal Chem 554 191 -199. 

Wang JX, Zhang JL, Adzic RR. 2007. Double-trap kinetic equation for the oxygen reduction reaction on Pt(lll) in acidic media. J Phys Chem A 111 12702-12710. 

Baranton S, Coutanceau C, Roux C, Hahn F, Leger JM. 2005. Oxygen reduction reaction in acid medium at iron phthalocyanine dispersed on high surface area carbon substrate tolerance to methanol, stability and kinetics. J Electroanal Chem 577 223-234. 

The impedance polarization performance of LSM electrode is closely related to the mechanism and kinetics of the oxygen reduction reactions. 02 reduction at SOFC cathodes is the most heavily studied subject, and this subject is sufficiently broad and complex to warrant its own review. Interested readers should consult the recent excellent articles by Adler [1] and Fleig [55], Here, only the polarization performance and its influencing factors are discussed. 

The kinetics of the four electron oxygen reduction reaction at Pt are limited by the very low exchange... 

These kinetic expressions represent the hydrogen oxidation reaction (HOR) in the anode catalyst layer and oxygen reduction reaction (ORR) in the cathode catalyst layer, respectively. These are simplified from the general Butler-Volmer kinetics, eq 5. The HOR... 

An electrocatalytic reaction is an electrode reaction sensitive to the properties of the electrode surface. An electrocatalyst participates in promoting or suppressing an electrode reaction or reaction path without itself being transformed. For example, oxygen reduction electrode kinetics are enhanced by some five orders of magnitude from iron to platinum in alkaline solutions or from bare carbon to carbon electrodes modified with Fe phthalocyanines or phenylporphyrins. For a comprehensive discussion of the subject, the reader is referred to refs. (76, 95, and 132-136). 

The Space Charge Layer of Galena and the Kinetics of the Oxygen Reduction Reaction. The reduction of oxygen on the surface... 

The capability of SECM to detect and to image regions with different catalytic activities is well known [120-122]. So far, this technique has been applied to studies of mainly two electrocatalytic reactions, the hydrogen oxidation reaction (HOR) and the oxygen reduction reaction (ORR), which have important implications for fuel cells. Unlike reversible redox mediators usually employed in SECM experiments, the kinetics of oxygen and hydrogen reactions are strongly dependent on the catalytic activity of the substrate surface. 

A final example of electrochemical kinetics will consider a return of the Pt WE from before but now exposed to a neutral (pH 7.2) solution into which oxygen is bubbled. The kinetics of the oxygen reduction reaction (ORR) will be studied. The data generated might appear as shown in Fig. 24. The reversible potential for the ORR in pH 7 solution, according to the Nernst equation, is... 

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