Preparation and characterization of graphite fluorometallate salts and graphite fluorides by chemical and electrochemical methods

Technical Report · Thu Sep 01 04:00:00 EDT 1988

OSTI ID:6809603

Lerner, M M

Graphite intercalation compounds of main-group metal fluorides are prepared utilizing Cl/sub 2/ as an oxidizing agent. The action of Cl/sub 2/ with GeF/sub 4/ and Cl/sub 2//HF with either PF/sub 5/ or BF/sub 3/ on graphite produces fluorometallate salts. The relationship between the calculated enthalpy change for the reduction half-reaction and degree of intercalation is discussed. The electrochemical oxidation of graphite in 49% aqueous HF generates, at the oxidation limit, a 2nd stage graphite fluoride with a charge on carbon of C/sub 10/minus/14//sup /plus//. The fully-oxidized product is a 2nd stage analog of the planar-sheet graphite fluorides produced by the chemical or electrochemical fluorination of graphite in liquid anhydrous hydrogen fluoride (AHF). The fluorometallate salts prepared by electrochemical oxidation of graphite in an AHF/alkali metal fluorometallate salt (M = As, P, B, Sn) electrolyte are examined. The chemical fluorination of 2nd- and 3rd-stage C/sub x/AsF/sub 6/ salts with AHF/F/sub 2/ at ambient temperature produces a planar-sheet graphite fluoride phase with a C/F ratio as low as 1.3 along with a C/sub x/AsF/sub 6/ phase. The reaction of graphite with AHF/SnF/sub 4//F/sub 2/ results in the rapid disappearance of SnF/sub 4/, F/sub 2/ uptake, and color change of the solid from grey to blue-black. Graphite reacts with AHF/K/sub 2/MnF/sub 6/ in a stoichiometric ratio of at least 1 Mn for 6 C to produce MnF/sub 3/ and a C/sub x/F phase. The reaction of excess PF/sub 5/ with a well-evacuated C/sub x/BF/sub 4/ /center dot/ deltaBF/sub 3/ salt yields partial displacement of BF/sub 3/. When PF/sub 5/ /plus/ HF are employed, no BF/sub 3/ is displaced from the fluoroborate salt. 21 refs., 15 figs., 18 tabs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6809603
• Report Number(s): LBL-25860; ON: DE89000274
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
ARSENIC COMPOUNDS
ARSENIC FLUORIDES
BORON COMPOUNDS
BORON FLUORIDES
CARBON
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMISTRY
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTROCHEMISTRY
ELECTROLYTES
ELEMENTAL MINERALS
ELEMENTS
ENTHALPY
FLUORIDES
FLUORINATION
FLUORINE COMPOUNDS
GERMANIUM COMPOUNDS
GERMANIUM FLUORIDES
GRAPHITE
GRAVIMETRY
HALIDES
HALOGEN COMPOUNDS
HALOGENATION
HYDROFLUORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
MANGANESE COMPOUNDS
MANGANESE FLUORIDES
MANGANESE HALIDES
MINERALS
NONMETALS
OXIDATION
OXIDIZERS
PHOSPHORUS COMPOUNDS
PHOSPHORUS FLUORIDES
PHYSICAL PROPERTIES
REACTION KINETICS
SALTS
SOLUBILITY
SYNTHESIS
THERMODYNAMIC PROPERTIES
TIN COMPOUNDS
TIN FLUORIDES
TIN HALIDES
TRANSITION ELEMENT COMPOUNDS
YIELDS