Oxidation Modification of Fuorinated Graphite and Its Reaction Mechanism

In this paper, Hummers method was used to oxidize fluorinated graphite in order to study the modification mechanism. The chemical composition and microstructure of the products before and after the reaction were characterized and analyzed. Oxidized fluorinated graphite (OFG) obtained by oxidation has a thin layered structure and different oxygen content. The main mechanism of KMnO4 modification is that MnO3+ with Lewis acid property can catalyze the activation of the fluorocarbon bond, which breaks to form F ion. At the same time, the unsaturated carbon bond is oxidized, resulting in the increase of carbon oxygen bond content and the generation of some OFG nano fragments. With the increase in KMnO4 dosage, the fluorocarbon bond will be gradually catalyzed to react according to its activity while the unsaturated carbon bond is oxidized, finally there are still some isolated fluorocarbon bonds with weak activity.

Fluorination of Carbon Molecular Sieve as Cathode Material for Lithium Primary Batteries and its Characteristics

Fluorinated carbon (CFx) is a new material with good lubricity and resistance to high temperature and corrosion. Meanwhile, CFx has excellent electrochemical properties when used as the cathode of the lithium primary batteries. Here, a series of carbon molecular sieve (CMS) is fluorinated via gas-phase fluorination. The CMS treated at 1550 °C has better electrochemical properties after fluorination. The fluorinated products named CMSF deliver specific capacity reaching 796 mAh g-1, associated with discharge potentials exceeding 3.1 V (vs. Li/Li+). The discharge voltage of CMSF is about 0.4 V ~ 0.6 V higher than that of fluorinated graphite (GF), and its energy density is about 8% ~ 13% higher than that of GF. The CMSF with the better electrochemical performances than GF as well as its low cost and scalable product demonstrated its great potential practicability in the field of lithium primary batteries.

Redox reactions between acetonitrile and nitrogen dioxide in interlayer space of fluorinated graphite matrices

The interlayer space of 2D materials can be a slit reactor where the transformations not typical for the gas phase occur. We report redox reactions involving acetonitrile and nitrogen oxides...

Chemiresistive Properties of Imprinted Fluorinated Graphene Films

The electrical conductivity of graphene materials is strongly sensitive to the surface adsorbates, which makes them an excellent platform for the development of gas sensor devices. Functionalization of the surface of graphene opens up the possibility of adjusting the sensor to a target molecule. Here, we investigated the sensor properties of fluorinated graphene films towards exposure to low concentrations of nitrogen dioxide NO2. The films were produced by liquid-phase exfoliation of fluorinated graphite samples with a composition of CF0.08, CF0.23, and CF0.33. Fluorination of graphite using a BrF3/Br2 mixture at room temperature resulted in the covalent attachment of fluorine to basal carbon atoms, which was confirmed by X-ray photoelectron and Raman spectroscopies. Depending on the fluorination degree, the graphite powders had a different dispersion ability in toluene, which affected an average lateral size and thickness of the flakes. The films obtained from fluorinated graphite CF0.33 showed the highest relative response ca. 43% towards 100 ppm NO2 and the best recovery ca. 37% at room temperature.