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Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch

Synthesis of graphene materials in a plasma stream from an up to 40 kW direct current (DC) plasma torch is investigated. These materials are created by means of the conversion of hydrocarbons under the pressure 350–710 Torr without using catalysts, without additional processes of inter-substrate tra...

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Autores principales: Shavelkina, Marina, Ivanov, Peter, Bocharov, Aleksey, Amirov, Ravil
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7178695/
https://www.ncbi.nlm.nih.gov/pubmed/32272737
http://dx.doi.org/10.3390/ma13071728
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author Shavelkina, Marina
Ivanov, Peter
Bocharov, Aleksey
Amirov, Ravil
author_facet Shavelkina, Marina
Ivanov, Peter
Bocharov, Aleksey
Amirov, Ravil
author_sort Shavelkina, Marina
collection PubMed
description Synthesis of graphene materials in a plasma stream from an up to 40 kW direct current (DC) plasma torch is investigated. These materials are created by means of the conversion of hydrocarbons under the pressure 350–710 Torr without using catalysts, without additional processes of inter-substrate transfer and the elimination of impurities. Helium and argon are used as plasma-forming gas, propane, butane, methane, and acetylene are used as carbon precursors. Electron microscopy and Raman imaging show that synthesis products represent an assembly of flakes varying in the thickness and the level of deformity. An occurrence of hydrogen in the graphene flakes is discovered by X-ray photoelectron spectroscopy, thermal analysis, and express-gravimetry. Its quantity depends on the type of carrier gas. Quasi-one-dimensional approach under the local thermodynamic equilibrium was used to investigate the evolution of the composition of helium and argon plasma jets with hydrocarbon addition. Hydrogen atoms appear in the hydrogen-rich argon jet under higher temperature. This shows that solid particles live longer in the hydrogen-rich environment compared with the helium case providing some enlargement of graphene with less hydrogen in its structure. In conclusion, graphene in flakes appears because of the volumetric synthesis in the hydrogen environment. The most promising directions of the practical use of graphеne flakes are apparently related to structural ceramics.
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spelling pubmed-71786952020-04-28 Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch Shavelkina, Marina Ivanov, Peter Bocharov, Aleksey Amirov, Ravil Materials (Basel) Article Synthesis of graphene materials in a plasma stream from an up to 40 kW direct current (DC) plasma torch is investigated. These materials are created by means of the conversion of hydrocarbons under the pressure 350–710 Torr without using catalysts, without additional processes of inter-substrate transfer and the elimination of impurities. Helium and argon are used as plasma-forming gas, propane, butane, methane, and acetylene are used as carbon precursors. Electron microscopy and Raman imaging show that synthesis products represent an assembly of flakes varying in the thickness and the level of deformity. An occurrence of hydrogen in the graphene flakes is discovered by X-ray photoelectron spectroscopy, thermal analysis, and express-gravimetry. Its quantity depends on the type of carrier gas. Quasi-one-dimensional approach under the local thermodynamic equilibrium was used to investigate the evolution of the composition of helium and argon plasma jets with hydrocarbon addition. Hydrogen atoms appear in the hydrogen-rich argon jet under higher temperature. This shows that solid particles live longer in the hydrogen-rich environment compared with the helium case providing some enlargement of graphene with less hydrogen in its structure. In conclusion, graphene in flakes appears because of the volumetric synthesis in the hydrogen environment. The most promising directions of the practical use of graphеne flakes are apparently related to structural ceramics. MDPI 2020-04-07 /pmc/articles/PMC7178695/ /pubmed/32272737 http://dx.doi.org/10.3390/ma13071728 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Shavelkina, Marina
Ivanov, Peter
Bocharov, Aleksey
Amirov, Ravil
Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title_full Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title_fullStr Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title_full_unstemmed Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title_short Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch
title_sort distinctive features of graphene synthesized in a plasma jet created by a dc plasma torch
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7178695/
https://www.ncbi.nlm.nih.gov/pubmed/32272737
http://dx.doi.org/10.3390/ma13071728
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