Electrical Resistance of Modified Thermo-exfoliated Graphite

The relationship between the structure parameters of modified by metals nanoparticles thermo-exfoliated graphite, as well as between methods of surface modification and the concentration of metal in graphite and the electrical resistance of bulk specimens of modified thermo-exfoliated graphite has been investigated. The modification of thermo-exfoliated graphite by metals has been performed by the two methods. According to the first method, graphite simultaneously has been exfoliated and modified in the cyclone gas-fired furnace at the temperature 1100 ℃. This method allowed to obtain thermo-exfoliated graphite with the concentration of modifier up to 5% mass. For the second method, graphite was previously thermo-exfoliated and then modified by reducing the metal from the corresponding metal salts. The bulk specimens with different values of density and porosity have been prepared by the method of cold pressing without binder from obtained powders of modified thermo-exfoliated graphite. Experimental studies of the electrical resistance of bulk specimens of modified thermo-exfoliated graphite along different directions allowed to establish the regularities of the change in conductivity depending on the porosity and density of the specimens, as well as the concentration of the metal modifier.