Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers

Autor: Ernst Z. Kurmaev, A Kiryakov, Lucía Fernández-García, A. F. Zatsepin, Andrey I. Kukharenko, Ivan S. Zhidkov, Seif O. Cholakh, Danil W. Boukhvalov, Jose Menendez
Přispěvatelé: Ministry of Education and Science of the Russian Federation, Russian Foundation for Basic Research, Jiangsu Province Science Foundation for Youths
Jazyk: angličtina
Rok vydání: 2021
Předmět:
VALENCE BANDS
Materials science
ELECTRONIC STRUCTURE
BI-LAYER
Electronic structure
QUANTUM DOTS
Molecular physics
DFT
law.invention
symbols.namesake
Carbon nanofibers
law
DENSITY-FUNCTIONAL-THEORY
CARBON NANOFIBRES
XPS
General Materials Science
NANOCARBONS
X RAY PHOTOELECTRON SPECTROSCOPY
DENSITY FUNCTIONAL THEORY
VALENCE BAND SPECTRA
Spectroscopy
Materials of engineering and construction. Mechanics of materials
Photoluminescence
Valence (chemistry)
Nano Express
Carbon nanofiber
Graphene
Quantum dots
OPTICAL DATA PROCESSING
CORE-LEVEL SPECTRA
ELECTRONIC.STRUCTURE
Condensed Matter Physics
CARBON NANOFIBERS
Nanocarbons
CALCULATIONS
NANOCRYSTALS
Covalent bond
TA401-492
symbols
Density functional theory
PHOTOLUMINESCENCE
X RAY PHOTOEMISSION SPECTROSCOPY
Raman spectroscopy
SEMICONDUCTOR QUANTUM DOTS
FIRST-PRINCIPLES MODELING
OPTICAL SPECTROSCOPY
Zdroj: Nanoscale Res. Lett.
Nanoscale Research Letters
Scopus
Digital.CSIC. Repositorio Institucional del CSIC
instname
RUO. Repositorio Institucional de la Universidad de Oviedo
Nanoscale Research Letters, Vol 16, Iss 1, Pp 1-8 (2021)
Popis: We report results of comprehensive experimental exploration (X-ray photoemission, Raman and optical spectroscopy) of carbon nanofibers (CNFs) in combination with first-principles modeling. Core-level spectra demonstrate prevalence of sp2 hybridization of carbon atoms in CNF with a trace amount of carbon–oxygen bonds. The density functional theory (DFT)-based calculations demonstrated no visible difference between mono- and bilayers because σ-orbitals are related to in-plane covalent bonds. The influence of the distortions on π-peak is found to be significant only for bilayers as a result of π–π interlayer bonds formation. These results are supported by both experimental Raman and XPS valence band spectra. The combination of optical measurements with a theoretical modeling indicates the formation of optically active graphene quantum dots (GQDs) in the CNF matrix, with a radiative relaxation of the excited π* state. The calculated electronic structure of these GQDs is in quantitative agreement with the measured optical transitions and provides an explanation of the absence of visible contribution from these GQDs to the measured valence bands spectra.
XPS measurements calculations are supported by Ministry of Science and Education of Russian Federation: Theme “Electron” № AAAA-A18-118020190098-5 and Project FEUZ-2020-0059. Optical measurements were additionally supported by RFBR project № 20-42-660012 and RSF project № 21-12-00392. DWB acknowledges the support from Jiangsu innovative and Entrepreneurial Talents Project.
Databáze: OpenAIRE
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