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arXiv · 1403.4920

Shungite in view of neutron scattering

Elena F. Sheka·Natalia N. Rozhkova·Krystina Holderna-Natkaniec·Ireneush Natkaniec
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Abstract

Recently suggested new concept of shungite (Int. J. Smart Nano Mat. DOI: 10.1080/19475411.2014.885913) exhibits this carboneous raw material as a multi-level fractal structure of nanosize fragments of reduced graphene oxide (rGO). In view of the extraordinary importance of the rGO starting material for the current molecular graphene technology, the natural rGO deposits turns out to be quite challenging, making it highly necessary to prove the reliability of the proposed rGO concept of shungite. Once consistent with all the block of the available geological and physical-chemical data obtained during the last few decades, the concept nonetheless needs a direct confirmation in terms of the current graphene science. The first such acknowledgement has been received just recently when studying photoluminescence (PL) of shungite dispersions (arXiv:1308.2569v2 [cond-mat.mes-hall]). A close similarity of PL spectra of aqueous dispersion of shungite and those of synthetic graphene quantum dots of the rGO origin has been established. The current paper presents the next direct confirmation supplied with neutron scattering. Elastic neutron diffraction and inelastic neutron scattering have left no doubts concerning both graphene-like configuration and chemical composition of basic structural elements of shungite attributing the latter to rGO nanosize sheets with an average 11:1:3 (C:O:H) atomic content ratio. The experimental data are supplemented with quantum-chemical calculations that allowed suggesting a clear vision of the shungite structure at its first nanolevels.

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Elena F. Sheka, Natalia N. Rozhkova, Krystina Holderna-Natkaniec, Ireneush Natkaniec. 2014-03-31. Shungite in view of neutron scattering. https://arxiv.org/abs/1403.4920

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