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

Abstract

The evolution of paramagnetic properties of the fullerene soot (FS), fullerene black (FB), and their polymer composites Phenylon C-2/FS, FB has been studied using the electron paramagnetic resonance (EPR) method. For the first time, a drastic growth of the EPR signals in the FB, FS, and composite samples was observed under pumping out at temperatures T = 20 ÷ 300 °C, which is attributed to the interaction between carbon defects and adsorbed gas molecules, mainly oxygen.It is shown that the ensemble of paramagnetic centers in the FB, FS, and the composite is heterogeneous. This ensemble consists of three spin subsystems 1, 2, and 3 related with different structural elements. The subsystems give three corresponding contributions, L 1, L 2 and L 3, into the overall contour of the EPR signal. The most intensive and broad signal L 3 is caused by 2D electrons from the surface of carbon flakes. Theoretical calculations of the L 3 signal line shape were carried out, and the decay rate of the integral intensity has been obtained for each component L 1, L 2, and L 3 after the contact of the sample with the ambient air. The signal decay process in the bulk composite samples is much slower due to their low gas permeability at room temperature (RT).

Tunable Fulleretic Sodalite MOFs: Highly Efficient and Controllable Entrapment of C60 Fullerene via Mechanochemistry

“…The presence of fullerene guests in the cages of ZIF-8 is confirmed additionally by ESR spectroscopy. Off-the-shelf fullerene shows a weak, sharp ESR line with a g -value around g = 2.002 and the peak-to-peak line width around W pp ≈ 0.1 mT, due to defects in the fullerene structure − (Figure S21). While pristine ZIF-8 does not show this signal, both ESR investigated C 60 @ZIF-8 (15%) and C 60 @ZIF-8 (100%) exhibit a similar but broader W pp ≈ 0.2 mT fullerene line (Figure S21).…”

Recent Advances in Methods for the Recovery of Carbon Nanominerals and Polyaromatic Hydrocarbons from Coal Fly Ash and Their Emerging Applications

“…The detailed morphological analysis of fullerene revealed that some of the nanocarbons have fullerene-like structures, suggesting that the growth mechanism of nanocarbon is somewhat similar to that of fullerene. Further, some of the investigators observed fullerene-like soot in the nanocarbon sitting on the surface of aluminosilicate spheres of CFA, justifying that primary fullerene particles are arranged in a chain-like assembly [107]. Such fullerene-like structures shows multi-shelled structures, which are interlinked by evidence of the appearance of strongly bent graphene sheets or ribbons and double shells.…”

Influence of Carbon Fibres on Properties of Composites Based on Sulfaryl-BSP-7 Copolymer

“…However, low wear resistance hinders its widespread use in tribological compounds. It is known from the literature [12,13] that low-and high-modulus CF improve the tribological properties of aliphatic and aromatic polyamides, because of which the developed PCM is actively used in the agricultural, metallurgical and automotive industries instead of serial materials.…”