GRAPHITE FLUORIDES PREPARED AT ROOM-TEMPERATURE .1. SYNTHESIS AND CHARACTERIZATION

The authors previously investigated the intercalation reaction of metallic or non-metallic fluorides MF//n(IF//5, NbF//5, TaF//5, MoF//6, WF//6, ReF//6, BF//3,. . . ) with graphite in a fluorine atmosphere and no fluorination of the graphite lattice was detected. This paper shows that if this process is carried out in the presence of HF at room temperature, partial fluorination of graphite occurs and first-stage graphite fluoride products of formula CF//xM//y(0. 5 less than equivalent to x less than equivalent to 0. 9, 0. 06 greater than equivalent to yGREQ0. 02 and M is I, Cl, Br, Re, W, Mo or B) are obtained. The fluorine-richer products with x equals 0. 9 are obtained when the IF//7 or IF//5-F//2-HF system is used. X-ray diffraction and i. r. spectroscopy studies show that in these new compounds the planarity of graphene layers is preserved and C-F bonds are probably predominantly ionic in character. These results are different from those of (CF//x)//n prepared at high temperatures (chair structure and covalent C-F bonds).