Synthesis of fluorinated graphene oxide by using an easy one-pot deoxyfluorination reaction

The fluorination of two types of graphene oxides conducted by an easy and scalable deoxyfluorination reaction is reported. This reaction was carried out using diethylaminodifluorosulfinium tetrafluoroborate, a stable compound and an efficient reagent for replacing oxygenated functional groups of graphene oxide by fluoride. The graphene oxide produced by the Hummers’ method (GOH) showed lower reactivity than that produced by the Brodie's method (GOB). X-ray photoelectron spectroscopy indicated that the highest fluorination degree achieved was 4.7 at.% when GOB was used, and the C–F character corresponds to semi-ionic bonds. Additionally, a partial reduction of GO was concomitant with the functionalization reaction. The deoxyfluorination reaction changed the crystalline structure of GO, favoring the reconstruction of Csp structure of the graphene lattice and reducing the number of stacked layers. The fluorination led to the modification of the electronic band structure of this material, increasing the band gap from 2.05 eV for GOB to 3.88 eV for fluorinated GOB, while for GOH the low flurionation led to a slight increase of the band gap, from 3.48 eV to 3.57 eV.This research was supported by National Commission for Scientific and Technological Research (CONICYT), Chile, under Postdoctoral fellowship N 3170104 granted to H. Aguilar-Bolados, Vice Presidency of Research and Development (VID), Universidad de Chile, Chile, under project Enlaces NENL010/2017 granted to M. Yazdani-Pedram and Spanish Ministry of Science and Innovation (MICINN), Spain, under project MAT2016-81138-R.Peer Reviewe