Carbon monoxide, electrocatalysis

Potential Dependence of Elementary Chemical Reactions in Electrocatalysis Coupling of Carbon Monoxide and Hydroxyl Species... 

Gasteiger HA, Markovic NM, Ross PN Jr. 1996. Structural effects in electrocatalysis Electrooxidation of carbon monoxide on Pt3Sn single-crystal surfaces. Catal Lett 36 1-8. 

Watanabe M, Motoo S. 1975a. Electrocatalysis by ad-atoms. Part in. Enhancement of the oxidation of carbon monoxide on platinum by mthenium ad-atoms. J Electroanal Chem 60 275-283. 

Watanabe M, Shibata M, Motoo S. 1985. Electrocatalysis hy ad-atoms. PartXn. Enhancement of carbon monoxide oxidation on platinum electrodes by oxygen adsorbing ad-atoms (Ge, Sn, Pb, As, Sb and Bi). J Electroanal Chem 187 161-174. 

Lanthanides as modifiers to other oxides in aluminas In zirconias In iron oxide Lanthanide oxides in mixed oxides With aluminas With iron oxides With other transition metal oxides To maintain surface area To increase oxidation rates To increase methanation rates For conduction in electrocatalysis For ammonia synthesis promotion To provide sulfur oxides (SO.,) control For dehydrogenation in carbon monoxide reactions For oxidation... 

Alloy surfaces are of substantial importance in catalysis, such as in the hydrogenation of unsaturated hydrocarbons, Fisher-Tropsch synthesis, steam reforming of methane, and many other processes [41]. In electrocatalysis, they have recently received attention in relation to the development of CO-tolerant fuelcell catalysts [42]. In many of these processes, atomic hydrogen and carbon monoxide are the most important intermediates or poisons therefore, these two adsorbates have received a great deal of attention in theoretical and computational studies. 

Several cases involve the adsorption of reactants and products (shielding or blocking effects), but one interesting situation in electrocatalysis is that of the electrooxidation of an organic fuel such as methanol. It involves the formation of a carbon monoxide adsorbed residue that follows a progressive oxidation. We can first state that the reaction occurs without an electrocatalytic influence of the... 

The electrochemical oxidation of methanol has been extensively studied on pc platinum [33,34] and platinum single crystal surfaces [35,36] in acid media at room temperature. Methanol electrooxidation occurs either as a direct six-electron pathway to carbon dioxide or by several adsorption steps, some of them leading to poisoning species prior to the formation of carbon dioxide as the final product. The most convincing evidence of carbon monoxide as a catalytic poison arises from in situ IR fast Fourier spectroscopy. An understanding of methanol adsorption and oxidation processes on modified platinum electrodes can lead to a deeper insight into the relation between the surface structure and reactivity in electrocatalysis. It is well known that the main impediment in the operation of a methanol fuel cell is the fast depolarization of the anode in the presence of traces of adsorbed carbon monoxide. 

The first paper on methanol electrocatalysis under UHV conditions was published by Attard et al. [139] on the most active surface, Pt(110). Similar results to those on Pt(l 11) were found, that is, carbon monoxide and molecular hydrogen, but with a slightly larger methanol surface coverage of 9 = 0.10. It was the first time that methoxy species were proposed as intermediates and were different from the carbon monoxide or formyl species proposed earlier by Bagotskii et al. [140], However, traces of the formyl species were also detected on reconstructed Pt(l 10) using vibrational spectroscopy, which was able to co-adsorb this species with atomic oxygen [117]. 

Carbon Monoxide Carbon monoxide is a model adsorbate for studying molecular adsorption in catalysis and electrocatalysis. It is a major poisoning species in the oxidation of small organic... 

Anodic Reactions in Electrocatalysis -Oxidation of Carbon Monoxide... 

Anodic Reactions in Electrocatalysis -Oxidation of Carbon Monoxide, Fig. 1 Plot of a-top C-O band wavenumber versus the CO fractional surface coverage for (a) nanometer-sized Pt particles supported on pyrolytic carbon of Sibunit family and (b) Pt(557) = Pt [6(lll)x(100)] single crystal (Reproduced from Refs. [4, 17] with permission of the American Chemical Society)... 

The present section describes recent advances in electrocatalysis for anodic reactions in low-temperature fuel cells that use hydrogen/carbon monoxide, methanol, and ethanol as fuels in acidic media. Electrocatalysis in alkaline fuel cells are not discussed. 

SAUER ET AL. Electrocatalysis of Formic Acid and Carbon Monoxide 285... 

Lamy C, Leger J-M, Clavilier J, Parsons R. Structural effects in electrocatalysis. A comparative study of the oxidation of carbon monoxide, formic acid and methanol on single crystal platinum electrodes. J Electroanal Chem 1983 150 71-7. 

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