Graphite, fluorinated

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. 

Mote stable catalysts ate obtained by using fluorinated graphite or fluorinated alumina as backbones, and Lewis acid halides, such as SbF, TaF, and NbF, which have a relatively low vapor pressure. These Lewis acids ate attached to the fluorinated soHd supports through fluorine bridging. They show high reactivity in Friedel-Crafts type reactions including the isomerization of straight-chain alkanes such as / -hexane. 

A further advantageous modification of electrodes is claimed by Watanabe [154] for the Central Glass Co. Ltd. which uses anodes coated with a composite layer of nickel containing a dispersed eutectoid of PTFE particles or fluorinated graphite particles. The low surface energy nickel based composite is said to improve the yield of perfluorooctanesulphonyl fluoride to 40.5 % in ECF. 

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]).

Initial discharge potentials of fluorinated graphite oxides, prepared by the modified Staudenmaier method, were in the range of 3.20-3.35 V at a current density... 

Charge-discharge behavior of surface-fluorinated graphite... 

Table 4 shows the compositions of surface-fluorinated graphite samples, obtained by elemental analysis, and surface compositions calculated from the peak areas of... 

Binding energies of X-ray photoelectron spectra of surface-fluorinated graphite samples... 

Fig. 15. Charge capacities of 2 min-fluorinated graphite samples as a function of cycle number. original, 128°C, <0> 150 C, A 194 C, 9 256°C, 390°C, C 497 C (reproduced with permission from Electrochim. Acta, 44 (1999) 2879 [48]).

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