Synthesis and Characterization of Highly Fluorinated Graphite Containing sp² and sp³ Carbon

Katia Guérin (1) , J.-P. Pinhero (1) , M. Dubois (1) , Z. Fawal (1, 2) , F. Masin (2) , Rachid Yazami (3) , André Hamwi (1)

1 LMI - Laboratoire des Matériaux Inorganiques
2 Faculté des Sciences III
3 LEPMI - Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces

Highly fluorinated graphites were obtained by reaction of fluorine with graphite, at room temperature, in the presence of iodine pentafluoride and hydrogen fluoride. The re-fluorination between 100 and 600 °C yielded a series of fluorinated graphites with semi-ionic and covalent C−F bonds with varying amounts of sp²- and sp³-type carbon hybridization. Three types of materials have been generated: for re-fluorination lower than 400 °C, the C−F bond is still mainly semi-ionic and the carbon atoms are sp² coplanar; for re-fluorination temperatures between 400 and 550 °C, “hybrid” graphite fluorides characterized by two types of C−F bonds, semi-ionic and covalent, with sp² and sp³ carbon hybridization were found. For higher re-fluorination temperatures (between 550 and 600 °C), despite a similar fluorination amount and a covalent C−F bond, the sp² character never completely vanished even at a high re-fluorination temperature of 600 °C. At such a temperature, a directly fluorinated graphite would be of the pure sp³ type.

Domaines: Matériaux

Katia Guérin, J.-P. Pinhero, M. Dubois, Z. Fawal, F. Masin, et al.. Synthesis and Characterization of Highly Fluorinated Graphite Containing sp² and sp³ Carbon. Chemistry of Materials, 2004, 16 (9), pp. 1786-1792. ⟨10.1021/cm034974c⟩. ⟨hal-00417851⟩