Premium
On the transition of reaction pathway during microwave plasma gas‐phase synthesis of graphene nanosheets: From amorphous to highly crystalline structure
Author(s) -
Toman Jozef,
Jašek Ondřej,
Šnírer Miroslav,
Pavliňák David,
Navrátil Zdeněk,
Jurmanová Jana,
Chudják Stanislav,
Krčma František,
Kudrle Vít,
Michalička Jan
Publication year - 2021
Publication title -
plasma processes and polymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 74
eISSN - 1612-8869
pISSN - 1612-8850
DOI - 10.1002/ppap.202100008
Subject(s) - graphene , amorphous solid , fourier transform infrared spectroscopy , microwave , decomposition , materials science , analytical chemistry (journal) , chemical engineering , chemistry , nanotechnology , organic chemistry , physics , quantum mechanics , engineering
Fourier‐transform infrared spectroscopy and proton‐transfer‐reaction–mass spectrometry are used in a complementary way to study gas‐phase processes during decomposition of ethanol in a microwave plasma torch. Decomposition products (C, C 2 and simple hydrocarbons) reassemble into higher hydrocarbons and graphene nuclei and further grow into graphene nanosheets (GNS). Depending on microwave power, ethanol flow rate and molecular gas admixture, the material structure changes from amorphous to crystalline. The presence of C 2 n + 1 H y species was found to be responsible for the formation of defects in the GNS structure. O 2 and H 2 admixtures change the gas temperature axial profile and consequently modify reaction pathways influencing growth and production rate of GNS. Determination of reaction pathway selectivity enables us to predict whether high‐quality or defective GNS are produced.