Carbonate, electrochemistry

In spite of the high effort focused on the carbon electrochemistry, very little is known about the electrochemical preparation of carbon itself. This challenging idea appeared in the early 1970s in connection with the cathodic reduction of poly(tetrafluoroethylene) (PTFE) and some other perfluorin-ated polymers. The standard potential of the hypothetical reduction of PTFE to elemental carbon ... 

Reaction 5.1 is meant to represent a nonspecific electrostatic interaction (presumably responsible for double-layer charge accumulation) Reaction 5.2 symbolizes specific adsorption (e.g., ion/dipole interaction) Reaction 5.3 represents electron transfer across the double layer. Together, these three reactions in fact symbolize the entire field of carbon electrochemistry electric double layer (EDL) formation (see Section 5.3.3), electrosorption (see Section 5.3.4), and oxidation/reduction processes (see Section 5.3.5). The authors did not discuss what exactly >C, represents, and they did not attempt to clarify how and why, for example, the quinone surface groups (represented by >CxO) sometimes engage in proton transfer only and other times in electron transfer as well. In this chapter, the available literature is scrutinized and the current state of knowledge on carbon surface (electrochemistry is assessed in search of answers to such questions. 

For the better or for worse, Frumkin s electrochemical theory of adsorption has played an important role in carbon electrochemistry research, especially in the prolific literature from the former Soviet Union. It can be summarized as follows [80,81] ... 

How much Conway appears to be out of touch with carbon (electrochemistry research is confirmed by his discussion of a 1972 paper by Thrower, presumably published in J Electroanal Chem anyone familiar with Peter Thrower s expertise—and that means any serious carbon researcher—knows that such a paper cannot (and does not ) exist. Finally, in the light of recent proposals regarding the edge chemistry of carbon surfaces [6], Conway s conclusion that [m]any porous or powder[ed] carbon materials have dangling surface bonds which are associated with free-radical behavior should also be viewed with caution (see Figure 5.4). Therefore, perhaps the most (and only ) reliable take-home message from this review is that much basic research of a substantive kind is required to relate the electrochemical behavior of various preparations more quantitatively to... (5) the surface chemistry of carbon preparations and their shelf-life stability, cycle life, and self-discharge characteristics. ... 

In assembling this volume, it is only natural that we have included another contribution from Poland, with its long tradition of expertise in the surface properties and behavior of carbon materials (see also Vols. 21 and 22). Drs. Biniak, Swi tkowski, and Pakula have prepared a particularly timely review of carbon electrochemistry, a much needed follow-up on a call-to-action chapter by Leon y Leon and Radovic in Vol. 24. There is great interest today, and many unanswered questions remain, regarding the virtues of specific carbon materials as electrodes and in electroanalysis, electrosynthesis, electrosorption, and electro-... 

Nakagawa, K. Ohashi, T. A reversible change between lithium zirconate and zirconia in molten carbonate. Electrochemistry 1999,67 (6), 618-621. 

In the liquid phase the topics of principal concern are adsorption and proton and/or electron transfer across the electric donble layer. Carbon materials are unique in these applications becanse they are insolnble over the entire practical range of pH, are amphoteric, and can exhibit either acidic or basic properties this was illustrated in Fignre 1.10. Furthermore, because of their more or less extensive delocalized k-electron system in the graphene layer, they can either accept or donate electrons. Snch remarkable flexibility offers, on the one hand, a nniqne opportnnity to tailor carbon s properties to specific needs in adsorption, catalysis, and electrocatalysis but, as argued in detail elsewhere [24], it is also responsible for the persistent lack of fundamental nnderstanding in the increasingly important field of carbon electrochemistry, despite the tremendous amount of research and development focused on carbon-based capacitors, batteries, and fnel cells. 

To date, carbon materials play a major role in nanosciences (fullerenes, nanotubes), electronic industry (diamond), metallurgy (graphitic carbon), electrochemistry, catalysis, adsorption, etc, The majority of these applications have arisen because of the existence of a superficial layer of chemically bonded elements. Thus, the surface functional groups determine the self-organization, the chemical stability and the reactivity in adsorptive and catalytic processes. 

Campana, F. P., M. Hahn, A. Foelske, P. Ruch, R. Kotz, and H. Siegenthaler. 2006. Intercalation into and film formation on pyrolytic graphite in a supercapacitor-type electrolyte (C2H5)4NBF4/propylene carbonate. Electrochemistry Communications 8 1363-1368. 

Takehara, M., Tsukimori, N. Nanbu, N. Ue, M. Sasaki, Y, Physical and electrolytic properties of fluoroethyl methyl carbonate. Electrochemistry 2003, 71, 1201-1204. 

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