English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/207844
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Investigating the possible origin of Raman bands in defective sp2/sp3 carbons below 900 cm−1: Phonon density of states or double resonance mechanism at play?

AuthorsPardanaud, Cedric; Cartry, Gilles; Lajaunie, Luc; Arenal, Raul; Buijnsters, Josephus Gerardus
KeywordsRaman microscopy
Phonon density of states
Double resonance mechanism
Amorphous carbon
Implanted graphite
Issue Date2019
PublisherMultidisciplinary Digital Publishing Institute
CitationC 5(4): 79 (2019)
AbstractMultiwavelength Raman spectroscopy (325, 514, 633 nm) was used to analyze three different kinds of samples containing sp2 and sp3 carbons: chemical vapor deposited diamond films of varying microstructure, a plasma-enhanced chemical vapor deposited hydrogenated amorphous carbon film heated at 500 °C and highly oriented pyrolytic graphite exposed to a radio-frequent deuterium plasma. We found evidence that the lower part of the phonon density of states (PDOS) spectral region (300–900 cm−1) that rises when defects are introduced in crystals can give more information on the structure than expected. For example, the height of the PDOS, taken at 400 cm−1 and compared to the height of the G band, depends on the sp2 content, estimated by electron energy-loss spectroscopy. This ratio measured with 633 nm laser is more intense than with 514 nm laser. It is also correlated for diamond to the relative intensity ratio between the diamond band at 1332 cm−1 and the G band at ≈1500–1600 cm−1 when using 325 nm laser. Moreover, it is found that the shape of the PDOS of the exposed graphite samples is different when changing the wavelength of the laser used, giving evidence of a double resonance mechanism origin with the rise of the associated D3, D4 and D5 bands, which is not the case for a-C:H samples.
DescriptionThis article belongs to the Special Issue Characterization of Disorder in Carbons.
Publisher version (URL)https://doi.org/10.3390/c5040079
Appears in Collections:(ICMA) Artículos
Files in This Item:
File Description SizeFormat 
ivestigaplay.pdf1,29 MBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.