Nanocomposites and nanomaterials

Structure and optical properties of nanostructured CNx–Diamond core/shell
Pas’ko M.1, Fesenko O.2, Liedienov N.A.3,4, Pashkevich Yu.4, Prudnikov А.4, Pashchenko A.V.3,4, Levchenko G.G.3,4
1 Donetsk National Medical University named after M. Gorky.
Kirova Str., 27, Krasny Lyman-84404, Ukraine.
2 Institute of Physics, NASU. Prospect Nauki, 46, Kyiv-03028, Ukraine.
3 International Centre of Future Science, State Key Laboratory of Superhard Materials of Jilin University. Qianjin Str., 2699, Changchun-130012, China.
E-mail: nikita.ledenev.ssp@gmail.com
4 Donetsk Institute for Physics and Engineering named after O. O. Galkin, NASU. Prospect Nauki, 46, Kyiv-03028, Ukraine.

Currently, multilayer onion-like nanografites attract much attention due to their unique structural and physical properties which differ from the properties of other nanoscale carbon materials such as nanodiamonds, graphene, fullerenes and carbon nanotubes. The structure of onion-like nanografites is described as several imperfect fullerene-like layers or concentric graphite shells embedded into each other with the center consisting of a nanodiamond core, a cavity, or an ideal fullerene.
One of the most common methods for obtaining onion-like nanografites is anneal of ultra-fine diamond nanodiamond (~ 2500 °C) with a size of 4–5 nm in an inert atmosphere. The particles of onion-like nanografites obtained this method consist of very imperfection quasi-concentric shells of the sp2 carbon phase embedded into each other. Thermal anneal of the onion-like nanografites with a nanodiamond core at T ≥ 2000 °C leads to a graphitization of diamond nanocrystals, and even to their complete disappearance. It has been shown that pulsed laser anneal of carbon nitride doped ultra-dispersed diamond leads to the formation of onion-like nanografites with the nanodiamond core at room temperature. It has been also found that other hybrid (Eu@CNx) luminescent nanodiamond materials exhibit unique properties in luminescence intensity. Doping various impurities allows to obtain luminescent micro and nanocrystals of diamonds which can be perspective for application them in quantum photonics, computer science, optical microscopy, and sensor science.