Electrical properties of room temperature fluorine-intercalated graphite fibers
1991; Elsevier BV; Volume: 40; Issue: 2 Linguagem: Inglês
10.1016/0379-6779(91)91774-5
ISSN1879-3290
AutoresA. Tressaud, P. Dordor, E. Marquestaut, Paul Hagenmuller, Hiroyuki Fujimoto, S. Flandrois,
Tópico(s)Advancements in Battery Materials
ResumoFluorine-intercalated graphite fibers have been synthesized at room temperature by direct reaction with elemental fluorine. The host materials were either vapor-grown fibers or pitch-based fibers. The CxF compounds obtained were mostly of the stage-3 type with a 12.65 Å repeat distance. The carbon-to-fluorine atomic ratio ranged from 10 to 14. Resistivity measurements carried out between 4.2 and 300 K show clearly that the fluorination reduces the resistivity values, whatever the type of pristine material. For fluorine-intercalated pitch-based fibers an anomalous increase of resistivity below 30 K may be consistent with a weak electronic localization or with two-dimensional carrier-carrier interaction effects. In fluorine-intercalated vapor-grown fibers the anomalous bump observed around 190 K could result from a phase transition. The room temperature value of the conductivity of this type of material, i.e. σ = 1.6 × 105 S cm−1, is one of the highest ever observed for fluorine-intercalated CxF fibers.
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