Electrical, magnetic and structural characterization of fullerene soots

Abstract

Due to an oversight, the captions for figures 1 and 2 were transposed. The correct figure captions are given below. Figure 1. A transmission electron micrograph of 50 Torr He fullerene soot showing coagulated balloons which are suggested to be sealed containers of defective free radical material. Notice that the shape of the particles suggests that the balloons contain several structures held together initially by Van der Waals forces and then sealed by a number of coats of carbon atoms in the gas phase. Figure 2. Small-aperture transmission electron diffraction of 50 Torr He soot. The spot pattern shown is consistent with a collection of randomly orientated graphitic microcrystallites as shown in figure 3.

Paramagnetic Properties of Fullerene-Derived Nanomaterials and Their Polymer Composites: Drastic Pumping Out Effect

“…6 and Table 1 ), which indicates on the modification of the material structure. This result is consistent with the data [ 25 , 27 ], where a change was also observed in the structure of the FS [ 25 ] and paramagnetic properties of FB [ 27 ] in the course of high-temperature annealing.…”

“…The nature of paramagnetic defects of carbonaceous materials (carbon nano-onion, graphene, fullerenes and fullerene-derived materials, astra lens, and so on) has been widely discussed over the past decade [ 23 – 31 , 33 – 36 , 41 ]. Fullerenes can contain defects of molecules C60 [ 40 , 42 ], FS, and FB—uncompleted sp 2 —or sp 3 valences, e.g., the edges of carbon fragments [ 25 – 27 , 36 ] or localized spins attributed to sp 3 dangling bonds between neighboring carbon sheets [ 29 ]. It is well known, that the molecular oxygen localized near carbon dangle bonds causes a noticeable broadening of the EPR signal.…”

“…The EPR spectroscopy is generally used to get detailed information about the electron properties of fullerene-like materials. The structure and paramagnetic properties of the fullerene soot (FS) and fullerene black (FB) were studied in [ 25 – 28 ]. The EPR signal of these materials is shown to be characterized by the following parameters: g = 2.0022 ÷ 2.0023, Δ H pp ≅ 2 G. The concentration of paramagnetic radicals N s ~10 21 g −1 and N s ~3 × 10 18 g −1 in the initial samples FS [ 25 ] and FB [ 27 ], has been found, respectively.…”

“…The structure and paramagnetic properties of the fullerene soot (FS) and fullerene black (FB) were studied in [ 25 – 28 ]. The EPR signal of these materials is shown to be characterized by the following parameters: g = 2.0022 ÷ 2.0023, Δ H pp ≅ 2 G. The concentration of paramagnetic radicals N s ~10 21 g −1 and N s ~3 × 10 18 g −1 in the initial samples FS [ 25 ] and FB [ 27 ], has been found, respectively. These parameters are changed insignificantly at the presence of molecular oxygen, except for FB samples, of which the N s value increases by the order of magnitude after evacuation at T = 150 °C [ 27 ].…”

“…These parameters are changed insignificantly at the presence of molecular oxygen, except for FB samples, of which the N s value increases by the order of magnitude after evacuation at T = 150 °C [ 27 ]. The results obtained for the soot were explained using a model where the fullerene soot particles are assumed to be encapsulated in the highly defective onion-like carbon (OLC) [ 25 ].…”