Carbon host

The electroinsertion reaction of mobile lithium ions into a solid carbon host proceeds according to the general reaction scheme... 

During electrochemical reduction (charge) of the carbon host, lithium cations from the electrolyte penetrate into the carbon and form a lithiated carbon Li rCn. The corresponding negative charges are accepted by the carbon host lattice. As for any other electrochemical insertion process, the prerequisite for the formation of lithiated carbons is a host material that exhibits mixed (electronic and ionic) conductance. 

Carbonate host altered carb. host carbonates... 

Paradis, S., Turner, W.A., Coniglio, M., Wilson, N. Nelson, J.L. 2006. Stable and radiogenic isotopic signatures of mineralized Devonian carbonates of the Northern Rocky Mountains and the Western Canada Sedimentary Basin. In Hannigan, P.K. (ed) Potential for carbonate-hosted lead-zinc Mississippi Valley-type mineralization in northern Alberta and southern Northwest Territories Geoscience Contributions,... 

We assume that no precipitation occurs, although this assumption will later be proved to be inadequate. Using a non-linear system is a complicated way of solving this particular problem, but this example is quite illustrative and can be extended to any number of components. Although ionized atoms like H+ and Ca2 + are natural components of the dilute solution under consideration, carbon and oxygen do not appear as such in natural systems. Since the group C032- is not destroyed in any reaction it will therefore be taken as the carbon host. The component matrix B is shown in Table 6.1. As explained above, the H20 row is subtracted from the OH-row, which is left with — 1 in the H + column, which produces the new component matrix of Table 6.2. 

In the intercalation reactions, ions (anions X or cations M+) penetrate into the van der Waals gaps between the ordered carbon layers resulting in the enlargement of their inter-layer distance [23,24]. The corresponding charges are conducted by carbon and accepted into the carbon host lattice. 

Thirty-two soil samples on a N-S traverse were collected from the brunisolic B-horizon (20 cm average depth) in May, 2008 over the drill-defined Northeast Zone of the Gay s River carbonate hosted massive sulfide (CHMS) Zn-Pb deposit, Stewiacke, Nova Scotia. This mineral target is buried by up to 10 m of exotic till and c. 10 m of gypsum, and so represents an ideal location to evaluate the exploration performance levels of partial digestions designed to extract labile elements from soil particle surfaces. 

Distal exhalative manganese enriched stratigraphy to carbonate-hosted zinc deposits, Adirondack Lowlands, New York State, U.S.A. 

Irish-type SEDEX deposits are carbonate-hosted stratiform to stratabound sulfide deposits that occur as syngenetic exhalative to early diagenetic replacement bodies (Coleman et al. 1989). Many SEDEX deposits have formed in Proterozoic intracontinental rifts and Phanerozoic deposits occur in similar... 

Foley, N. K. 2002. Chapter E, Environmental geochemistry of platform carbonate hosted sulfide deposits. In Seal II, R. R. Foley, N. K. (eds) Progress on Geoenvironmental Models for... 

In lithium rechargeable batteries carbon materials are used that function as a lithium reservoir at the negative electrode. Reversible intercalation, or insertion, of lithium into the carbon host lattice avoids the problem of lithium dendrite formation and provides a large improvement in terms of cycleability and safety (111). 

The sieving effect of the carbon host was also demonstrated by measuring the capacitance values of an AC in a series of solvent-free ionic liquids (ILs) of increasing cation size [17], Since ions are not solvated in pure ILs, it was easy to interpret the electrochemical properties by comparing the nanoporous characteristics of carbon and the size of cations calculated by molecular modeling. It was found that the overall porosity of the carbon is noticeably underused, due to pores smaller than the effective size of the cations. The results with ILs confirm that the optimal pore size depends on the kind of electrolyte, i.e., the dimensions of pores and ions must match each other. 

From the researches achieved recently, three main breakthroughs might be observed. The first one concerns the traditional concept of EDL in a nanoporous carbon. It has been demonstrated from independent experiments performed by few groups that the highest capacitance related with electrosorption is observed when the nanopores of carbons perfectly fit the dimensions of ions. Some experiments have even shown some swelling of the carbon host which could be attributed to an intercalation/insertion-type penetration of ions. Moreover, the ions could penetrate desolvated in the pores. From the foreword, it is obvious that some computational work is now necessary for a better interpretation of these experimental observations. Especially, the energy calculations should... 

CLASSIFICATION OF ANODE CARBON HOST 12.2.1 Conventional Carbons... 

FIGURE 12.10 Charge-discharge profiles of MAG developed by Hitachi Co. In these profiles, charge indicates lithium intercalation into carbon host, and discharge indicates the deintercalation. (From Yoshito, I., Tanso, 225, 382, 2006. With permission.)... 

FIGURE 12.12 Comparisons of discharge capacity variation of MAG and typical graphitic carbons as a function of current density (a) and apparent electrode density (b). In these curves discharge represents the deintercalation from the carbon host. (From Endo, M., et al., Carbon, 39, 1287, 2001. With permission.)... 

---