Fluorinated graphite intercalates

Whereas superaeid (HF/BF3, HF/SbF, HF/TaF FS03FI/SbF3, etc.)-eatalyzed hydroearbon transformations were first explored in the liquid phase, subsequently, solid aeid eatalyst systems, sueh as those based on Nafion-H, longer-chain perfluorinated alkanesulfonic acids, fluorinated graphite intercalates, etc. were also developed and utilized for heterogeneous reactions. The strong acidic nature of zeolite catalysts was also successfully explored in cases such as FI-ZSM-5 at high temperatures. 

Discharge characteristics of fluorine-graphite intercalation compounds... 

Fig. 6. Galvanostatic discharge curves of button-type cells Li/1 M L1CIO4 + EC PC DME/LT—CFV, HT—CF, at 40 mAg 1. LT—CFV fluorine-graphite intercalation compound prepared at a low temperature, HT—CFV graphite fluoride prepared at a high temperature (reproduced with permission from J. Power Sources, 68 (1994) 708 [34]).

Group 14. - 3.14.1 Carbon. The bonding structure in amorphous carbon nitride has been studied by H, and NMR spectroscopy. A F NMR study of paramagnetism in fluorinated graphite has been reported. Carbon-fluorine bonding has been detected in fluorine-graphite intercalation compounds by and F NMR spectroscopy. ... 

Touhara, H. Suganuma, S. Okino, F., "Lithium Batteries with Fluorine-Graphite Intercalation Compound Cathodes. Post-Graphite Fluoride Cathode," Tanso 1991,150, 328. 

Nakajima, T., "Fluorine-Graphite Intercalation Compounds. Their Synthesis, Structures, and Physical and Chemical Properties," Tanso, 1990,145,295. 

TABLE 12.3 Fluorine/carbon atomic ratio, stage number and repeat distance 4 of fluorine-graphite intercalation compounds synthesized by various methods [189-192]... 

Figure 1 Fully optimized structures of the partially fluorinated graphite intercalation compounds with optimized Hj molecules (Adapted with permission from Ref 27. Copyright (2009) American Chemical Society.)...

It is used as a fluorinating reagent in semiconductor doping, to synthesi2e some hexafluoroarsenate compounds, and in the manufacture of graphite intercalated compounds (10) (see Semiconductors). AsF has been used to achieve >8% total area simulated air-mass 1 power conversion efficiencies in Si p-n junction solar cells (11) (see Solarenergy). It is commercially produced, but usage is estimated to be less than 100 kg/yr. 

Dining interaction at ambient temperature in a bomb to produce poly (carbon monofluoride), admission of fluorine beyond a pressure of 13.6 bar must be extremely slow and carefully controlled to avoid a violently exothermic explosion [1], Previously it had been shown that explosive interaction of carbon and fluorine was due to the formation and decomposition of the graphite intercalation compound, poly (carbon monofluoride) [2], Presence of mercury compounds prevents explosion during interaction of charcoal and fluorine [3], Reaction of surplus fluorine with graphite or carbon pellets was formerly used as a disposal method, but is no longer recommended. Violent reactions observed when an exhausted trap was opened usually involved external impact on the metal trap, prodding the trap contents to empty the trap, or possibly ingress of moist air... 

Xenon difluoride may be used as the pure reagent or as a graphite intercalate for the effective fluorination of polynuclear aromatics [86 87] (equations 49 and 50)... 

During interaction at ambient temperature in a bomb to produce poly(carbon monofluoride), admission of fluorine beyond a pressure of 13.6 bar must be extremely slow and carefully controlled to avoid a violently exothermic explosion [ 1 ]. Previously it had been shown that explosive interaction of carbon and fluorine was due to the formation and decomposition of the graphite intercalation compound, poly(carbon monofluoride)... 

Katinonkul, W., Lerner, M. M., Graphite intercalation compounds with large fluoroanions. Journal of Fluorine Chemistry 2007,128, 332-335. 

The discovery of what appears to be a thermodynamic threshold governing the intercalation of graphite by fluoro anions, MF,, has required the evaluation of the thermodynamic stability of a number of such species. Since germanium tetrafluoride and fluorine are intercalated, in combination, by graphite to form both GeFj" and GeFs ", the first and second fluoride ion affinities of that molecule are each of interest. Evaluation of the fluoride ion affinity of boron trifluoride by Altshuller yielded a value of-71 kcal moF. This has been accepted by several authors as the basis for other fluoride ion affinities and electron affinities. Sharpe, however, has preferred a value of -91 kcal moF, based upon the data of Bills and Cotton. Although this latter value is in harmony with other fluoride ion affinities and electron affinities, its confirmation was clearly desirable to provide a firm basis for correction of affinities based upon the lower value. This paper describes the studies that have provided these fluoride ion affinities. 

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