Investigation of Conductive Nanodisperse Carbon by Raman Scattering Spectroscopy

The Properties of Nanodispersed Carbon Black Particles After Thermal Treatment

“…Such increase (decrease) of fundamental phonon frequency seems to arise from intense changing of crystallites graphenic components boundary atoms chemical composition (possibly, decontamination or reconstruction). In the studied case (of normal valence vibration А 1g ), connected to D band, this frequency change occurs both after thermal oxidative [15] and after thermal treatment at the temperature range of 1100 -1600°С. These changes are of threshold nature and, for instance, after thermal treatment at the temperature higher than 2000 °С in the range of 2000 -3000 °С fundamental frequencies changes do not take place.…”

The effect of thermal-oxidative and thermal treatment on the structure and electrical conductivity properties of the carbon black particles

“…This is accompanied by merging of the graphene planes, which starts most likely from the surface layers. Such a mechanism of reducing the total electrical resistance of subsurface regions of the NGC particles is most probable because in this case the mobile π-electrons are delocalized in the graphene planes with increasing spatial extension along the L a direction A further increase in R with raising the temperature from 1600 to 2800 °C (at a progressive growth of L a ) is likely due to a change in the ratio of different configurations of edge atoms of the graphene planes on the particle surface and in subsurface zone in favor of the zig or armchair structures, which is followed by a partial return from 'metallic' conductivity to 'semiconductor' one [14,18]. At the same time, experiments showed that during thermal treatment in the range of 1600 to 2800 °C, similar to the previous range of 1000-1600 °C, there is a decrease in the intensity ratio of D and G bands, which is somewhat contrary to the observed changes in R for the studied powders (Fig.…”

“…For the deliberate modification of electrophysical properties during the synthesis and treatment of carbon powders, it is necessary to reveal the structural This work continues the development of physicochemical principles for the synthesis of conductive nanosized globular carbon, investigation of its properties, and creation of advanced functional carbon materials with improved characteristics, which are used, in particular, to devise highly efficient systems for electrical energy storage [12][13][14].…”

“…The effect of thermal-oxidative treatment (η, %) of NGC P 234 and thermal treatment (T, K) of NGC N 234[14] on the intensity ratio of D and G bands (ID/IG) in the Raman spectra of NGC samples: 1 -N 234, 2 -P 234.…”

Investigation of formation process of nanodispersed carbon black particles during hydrocarbon thermal treatment at short reaction time

“…Most effective, at this point, method of determining the crystallographic ordering of the nanodispersed carbon samples is Raman spectroscopy, which allows to explore the structure of samples using characteristic peaks in the spectrum of the Raman shift upon irradiation of the obtained carbon samples with a laser. The use of the technique of Raman spectroscopy in the study of the carbon particles described in [1,2].…”