Cargando…
Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers
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 ca...
Autores principales: | , , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Springer US
2021
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8505591/ https://www.ncbi.nlm.nih.gov/pubmed/34633574 http://dx.doi.org/10.1186/s11671-021-03595-y |
_version_ | 1784581566220992512 |
---|---|
author | Boukhvalov, D. W. Zhidkov, I. S. Kiryakov, A. Menéndez, J. L. Fernández-García, L. Kukharenko, A. I. Cholakh, S. O. Zatsepin, A. F. Kurmaev, E. Z. |
author_facet | Boukhvalov, D. W. Zhidkov, I. S. Kiryakov, A. Menéndez, J. L. Fernández-García, L. Kukharenko, A. I. Cholakh, S. O. Zatsepin, A. F. Kurmaev, E. Z. |
author_sort | Boukhvalov, D. W. |
collection | PubMed |
description | 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. |
format | Online Article Text |
id | pubmed-8505591 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | Springer US |
record_format | MEDLINE/PubMed |
spelling | pubmed-85055912021-10-27 Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers Boukhvalov, D. W. Zhidkov, I. S. Kiryakov, A. Menéndez, J. L. Fernández-García, L. Kukharenko, A. I. Cholakh, S. O. Zatsepin, A. F. Kurmaev, E. Z. Nanoscale Res Lett Nano Express 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. Springer US 2021-10-11 /pmc/articles/PMC8505591/ /pubmed/34633574 http://dx.doi.org/10.1186/s11671-021-03595-y Text en © The Author(s) 2021 https://creativecommons.org/licenses/by/4.0/Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . |
spellingShingle | Nano Express Boukhvalov, D. W. Zhidkov, I. S. Kiryakov, A. Menéndez, J. L. Fernández-García, L. Kukharenko, A. I. Cholakh, S. O. Zatsepin, A. F. Kurmaev, E. Z. Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title | Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title_full | Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title_fullStr | Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title_full_unstemmed | Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title_short | Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers |
title_sort | unveiling the atomic and electronic structure of stacked-cup carbon nanofibers |
topic | Nano Express |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8505591/ https://www.ncbi.nlm.nih.gov/pubmed/34633574 http://dx.doi.org/10.1186/s11671-021-03595-y |
work_keys_str_mv | AT boukhvalovdw unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT zhidkovis unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT kiryakova unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT menendezjl unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT fernandezgarcial unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT kukharenkoai unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT cholakhso unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT zatsepinaf unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers AT kurmaevez unveilingtheatomicandelectronicstructureofstackedcupcarbonnanofibers |