Thermal exfoliation of fluorinated graphite

Marc Dubois (1) , Katia Guérin (1) , Yasser Ahmad (1) , Nicolas Batisse (1) , Maimonatou Mar (1) , Lawrence Frézet (1) , Wael Hourani (2) , Jean-Luc Bubendorff (2) , Julien Parmentier (2) , Samar Hajjar-Garreau (2) , Laurent Simon (2)

1 ICCF - Institut de Chimie de Clermont-Ferrand
2 IS2M - Institut de Science des Matériaux de Mulhouse

The thermal exfoliation of graphite fluoride was investigated using two starting materials: fluorinated HOPG and powdered room temperature graphite fluoride (RTGF) post-treated in pure F2 gas in order to adjust the relative contents of intercalated species, the carbon hybridization and the C–F bonding. Firstly, the thermal exfoliation of HOPG sample (of composition CF0.57) at the nanoscale is highlighted using scanning tunneling microscopy (STM). Such process involves a defluorination, which is accelerated by disruption of the graphene sheets. Similar breaking occurs during the exfoliation of post-treated RTGF and evolves CF4 and C2F6 gases. Moreover, the exfoliation using a thermal shock is assisted by the fast deintercalation of the catalyst species in the region where the covalence of the C–F bonds is weakened. In such way, exfoliation occurs with the quasi-total defluorination.

Domaines: Chimie

Marc Dubois, Katia Guérin, Yasser Ahmad, Nicolas Batisse, Maimonatou Mar, et al.. Thermal exfoliation of fluorinated graphite. Carbon, 2014, 77, pp.688-704. ⟨10.1016/j.carbon.2014.05.074⟩. ⟨hal-01080740⟩