Oxygen, reductive chemistry

Wang, H. Xie, K, Investigation of Oxygen Reduction Chemistry in Ether and Carbonate Based Electrolytes for Li-02 Batteries. Electrochimica Acta 2012,64,29-34. 

H. Wang and K. Xie, Investigation of oxygen reduction chemistry in ether and carbonate based electrolytes for Li-Oj batteries, Electrochim. Acta 64,2012,29-34. 

Two processes, developed for the direct processing of lead sulfide concentrates to metallic lead (qv), have reached commercial scale. The Kivcet process combines flash smelting features and carbon reduction. The QSL process is a bath-smelting reactor having an oxidation 2one and a reduction 2one. Both processes use industrial oxygen. The chemistry can be shown as follows ... 

It is important to compare the catalytic properties of Prussian blue with known hydrogen peroxide transducers. Table 13.2 presents the catalytic parameters, which are of major importance for analytical chemistry selectivity and catalytic activity. It is seen that platinum, which is still considered as the universal transducer, possesses rather low catalytic activity in both H202 oxidation and reduction. Moreover, it is nearly impossible to measure hydrogen peroxide by its reduction on platinum, because the rate of oxygen reduction is ten times higher. The situation is drastically improved in case of enzyme peroxidase electrodes. However, the absolute records of both catalytic activity... 

Zhang, S., et al., Carbon nanotubes decorated with Pt nanoparticles via electrostatic self-assembly a highly active oxygen reduction electrocatalyst, journal of Materials Chemistry,... 

Hu, Y., et al., Bimetallic Pt-Au nanocatalysts electrochemically deposited on graphene and their electrocatalytic characteristics towards oxygen reduction and methanol oxidation. Physical Chemistry Chemical Physics, 2011.13(9) p. 4083-4094. 

Jeon, S., D. Kim, and M. Ahmed, Different length linkages of graphene modified with metal nanoparticles for oxygen reduction in acidic media. Journal of Materials Chemistry, 2012. 22(32) p. 16353-16360. 

Gebeyehu, N., et ah, Ultrathin Ti02-coated MWCNTs with excellent conductivity andsmsi nature as pt catalyst support for oxygen reduction reaction in PEMFCs. Journal of Materials Chemistry, 2012. 

J. of Electro-analytical Chemistry, 471 116- 125 King, F., Quinn, M. J., Litke, C. D., 1995. Oxygen reduction on copper in neutral NaCl solution. Journal of Electro-analytical Chemistry, 385(1) 45 - 55 Kneer, E. A., 1997. Electrochemical measurements during the CMP of Tungsten thin films. J. Electrochem. Soc., 144 3041 - 3049... 

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.)... 

Basura, V. L, Beattie, P. D. and Holdcroft, S. 1998. Solid-state electrochemical oxygen reduction at Pt —> Nation 117 and Pt —> BAM3G 407 interfaces. Journal ofElectroanalytical Chemistry 458 1-5. 

Zhang, L., Ma, C. and Mukerjee, S. 2004. Oxygen reduction and transport characteristics at a platinum and alternative proton conducting membrane interface. Journal of Electroanalytical Chemistry 568 273-291. 

Manganese is the third most abundant transition element [1]. It is present in a number of industrial, hiological, and environmental systems, representative examples of which include manganese oxide batteries [2] the oxygen-evolving center of photosystem II (PSII) [3] manganese catalase, peroxidase, superoxide dismutase (SOD), and other enzymes [4, 5] chiral epoxidation catalysts [6] and deep ocean nodules [7]. Oxidation-reduction chemistry plays a central role in the function of most, if not all, of these examples. 

Anderson and his coworker carried out a series quantum chemistry studies of oxygen reduction reactions.52-57 Anderson and Abu first studied reversible potential and activation energies for uncatalyzed oxygen reduction to water and the reverse oxidation reaction using the MP2/6-31G method. The electrode was modeled by a non-interacting electron donor molecule with a chosen ionization potential (IP). The primary assumption is that when the reactant reaches a point on the reaction path where its electron affinity (EA) matched the donor IP, an electron transfer is initialized. The donor s IP or reactant s EA was related to the electrode potential by,... 

The two cathodic partner reactions in corrosion are hydrogen evolution and oxygen reduction. Consider the Electrochemical Series (for a full list, see The Handbook of Chemistry and Physics) and work out a rule that gives the standard reversible electrode potential, less negative than which (pH 7 and aMzt = lO 6 M) a metal will no longer have a tendency to corrode (a) in 1 M acid and (b) in 1 M alkali. (Bockris)... 

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.)...

A detailed model for the oxygen reduction reaction at semiconductor oxide electrodes has been developed by Presnov and Trunov [341, 345, 346] based on concepts of coordination chemistry and local interaction of surface cation d-electrons at the oxide surface with HO, H20, and 02 acceptor species in solution. The oxygen reduction reaction is assumed to take place at active sites associated with cations at the oxide surface in a higher oxidation state. These cations would act as donor-acceptor reduction (DAR) sites, with acceptor character with respect to the solid by capture of electrons and donor electronic properties with respect to species in solution. At the surface, the long-range oxide structure is lost and short-range coordination by hydroxide ions and water molecules in three octahedral positions may occur [Fig. 16(b)], One hydroxide ion can compensate coulombically for the excess charge on surface M2+ cations with two coordinated water mole-... 

Of the various models which have been proposed for the oxygen electrode reactions, the model of Presnov and Trunov [341, 345] for oxygen reduction at semiconductor oxide electrodes deserves special mention. This model is based on concepts of coordination chemistry and local interaction of surface cation d-electrons with HO", H20, and 02 acceptor species in solution. 

Recent literature in the chemistry of calixpyrroles comprises the syntheses, characterization and complexation reactions of a series of binucleating Schiff-base calixpyrrole macrocycles <2007CEJ(A)3707> a study of the dynamics of calix[4]pyrrole and octafluorocalix[4]pyrrole as a function of the solvent and fluorine substitution <2007CEJ(A)1108> and oxygen reduction at dicobalt complexes of a Schiff base calixpyrrole ligand <2007AGE584>. 

It is anticipated that despite the specially favored environment provided for oxygen reduction by the protein the fundamental principles of chemistry in simple systems will apply to the enzyme. Thus, any proposed mechanism for the enzymic reduction of dioxygen will have to accommodate two electron steps leading sequentially to peroxide and water and provide a means to overcome the characteristic stability of the peroxide intermediate. 

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