Carbon dioxide electrocatalytic

Reduction of Carbon Dioxide Electrocatalytic Properties of Carbon 19... 

The electrocatalytic oxidation of methanol has been widely investigated for exploitation in the so-called direct methanol fuel cell (DMFC). The most likely type of DMFC to be commercialized in the near future seems to be the polymer electrolyte membrane DMFC using proton exchange membrane, a special form of low-temperature fuel cell based on PEM technology. In this cell, methanol (a liquid fuel available at low cost, easily handled, stored, and transported) is dissolved in an acid electrolyte and burned directly by air to carbon dioxide. The prominence of the DMFCs with respect to safety, simple device fabrication, and low cost has rendered them promising candidates for applications ranging from portable power sources to secondary cells for prospective electric vehicles. Notwithstanding, DMFCs were... 

Sullivan, B. P, K. Krist, and H. E. Guard, Eds., Electrochemical and Electrocatalytic Reactions of Carbon Dioxide, Elsevier, Amsterdam, 1993. 

Perhaps the most important paradigm in research on the mechanism of the electrocatalytic oxidation of small organic molecules is the dual pathway mechanism introduced in Capon and Parsons [1973a, b], and reviewed in Parsons and VanderNoot [1988]. In terms of methanol oxidation, the dual pathway may be summarized in a simplified way by Fig. 6.1. The idea is that the complete oxidation of methanol to carbon dioxide may follow two different pathways ... 

Poisoning of platinum fuel cell catalysts by CO is undoubtedly one of the most severe problems in fuel cell anode catalysis. As shown in Fig. 6.1, CO is a strongly bonded intermediate in methanol (and ethanol) oxidation. It is also a side product in the reformation of hydrocarbons to hydrogen and carbon dioxide, and as such blocks platinum sites for hydrogen oxidation. Not surprisingly, CO electrooxidation is one of the most intensively smdied electrocatalytic reactions, and there is a continued search for CO-tolerant anode materials that are able to either bind CO weakly but still oxidize hydrogen, or that oxidize CO at significantly reduced overpotential. 

Electrocatalytic reduction of carbon dioxide to Q-C3 hydrocarbons with less than 0.2% electrochemical yield was reported154 at pH 7 in the presence of pyrocatechol, TiCl3, and Na2Mo04 at -1.55 V versus SCE. 

Oxidation of Alcohols in a Direct Alcohol Fuel Cell The electrocatalytic oxidation of an alcohol (methanol, ethanol, etc.) in a direct alcohol fuel cell (DAFC) will avoid the presence of a heavy and bulky reformer, which is particularly convenient for applications to transportation and portable electronics. However, the reaction mechanism of alcohol oxidation is much more complicated, involving multi-electron transfer with many steps and reaction intermediates. As an example, the complete oxidation of methanol to carbon dioxide ... 

Low-valent rhenium complexes are effective in the catalytic reduction of carbon dioxide. The conversion can be accomplished photolytically or electrochemically and is of interest with regard to fuel production and greenhouse gas remediation [9]. Electrocatalytic reduction of CO2 to CO is initiated by the reduction of fac-Re(bpy)(CO)3Cl or a related complex and can be accomplished in homogeneous solution [54, 55] or on a polymer-modified electrode surface [56]. Catalytic current... 

The question of which part of the cathodic overpotential is to be attributed to true kinetic hindrance and which part must be attributed to poor conduction of the network of NiO-crystals which are forming the porous cathode and to mass transport hindrance of dissolved oxygen species and carbon dioxide in the porous cathode matrix is not yet answered. Therefore a clear indication of the importance of the electrocatalytic action of the cathode matrix cannot yet be given. 

Fisher and Eisenberg (107) have reported on the electrocatalytic reduction of carbon dioxide using macrocycle complexes of nickel and cobalt (e.g., complex 27). An indirect electrochemical reduction of C02 was ac-... 

Shibata H, Moulijn JA, Mul G. Enabling electrocatalytic Fischer-Tropsch synthesis from carbon dioxide over copper-based electrodes. Catal Lett. 2008 123 186-92. 

Morris AJ, McGibbon RT, Bocarsly AB. Electrocatalytic carbon dioxide activation the rate-determining step of pyridinium-catalyzed CO2 reduction. ChemSusChem. 2011 4 191-6. 

Gangeri M, Perathoner S, Caudo S, et al. Fe and Pt carbon nanotubes for the electrocatalytic conversion of carbon dioxide to oxygenates. Catal Today. 2009 143 57-63. 

Isse, A.A., Ferlin, M.G. and Gennaro, A. (2005a) Electrocatalytic reduction of arylethyl chlorides at silver cathodes in the presence of carbon dioxide Synthesis of 2-arylpropanoic acids. J. Electroanal. Chem. 581, 38 15. 

Fig. 18. Ligand architectures for coordinative carbon dioxide activation structure of the biotin-C02 coenzyme (17) involved in many biological carboxylations (146). Proposed pyridinium-COz adduct (18) accelerating electrocatalytic carbon dioxide reduction processes (147).

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