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arXiv · 1406.1703

Photonics of shungite quantum dots

Boris S. Razbirin·Natalia N Rozhkova·Elena F. Sheka
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Abstract

Shungite quantum dots are associated with nanosize fragments of reduced graphene oxide similarly to synthetic graphene quantum dots thus forming a common class of GQDs. Colloidal dispersions of powdered shungite in water, carbon tetrachloride, and toluene form the ground for the GQD photonic peculiarities manifestation. Morphological study shows a steady trend of GQDs to form fractals and a drastic change in the colloids fractal structure caused by solvent was reliably established. Spectral study reveals a dual character of emitting centers: individual GQDs are responsible for the spectra position while fractal structure of GQD colloids provides high broadening of the spectra due to structural inhomogeneity of the colloidal dispersions and a peculiar dependence on excitation wavelength. For the first time, photoluminescence spectra of individual GQDs were observed in frozen toluene dispersions which pave the way for a theoretical treatment of GQD photonics.

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Boris S. Razbirin, Natalia N Rozhkova, Elena F. Sheka. 2014-06-06. Photonics of shungite quantum dots. https://arxiv.org/abs/1406.1703

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