Titre :

Unveiling the nanostructured nature of pyrobitumen and shungite carbons through Raman, X-ray and theoretical analyses

Auteur(s) :

Faulques, Eric [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
EPItaxie et PHYsique des hétérostructures - IEMN [EPIPHY - IEMN]
Kalashnyk, Nataliya [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Nanostructures, nanoComponents & Molecules - IEMN [NCM - IEMN]
Lulzac, Yves [Auteur]
Moëlo, Yves [Auteur]
Institut des Matériaux de Nantes Jean Rouxel [IMN]

Titre de la revue :

Carbon Trends

Pagination :

10 pages

Éditeur :

Elsevier

Date de publication :

2024-12

ISSN :

2667-0569

Mot(s)-clé(s) en anglais :

Pyrobitumen ol Lopérec (France) Shungite of Karelia Graphitic carbon Nanostructure X-ray diffraction Raman scattering

Discipline(s) HAL :

Physique [physics]
Sciences de l'ingénieur [physics]

Résumé en anglais : [en]

<div><p>X-ray powder diffraction and multi-wavelength Raman spectroscopy were employed to characterize carbonaceous geomaterials, offering the first nanostructural analysis of rare pyrobitumen (LP) samples from the Lopérec ...
Lire la suite ><div><p>X-ray powder diffraction and multi-wavelength Raman spectroscopy were employed to characterize carbonaceous geomaterials, offering the first nanostructural analysis of rare pyrobitumen (LP) samples from the Lopérec gold deposit in Brittany, France, by comparing them to Karelian shungite (KS) and carbon allotropes samples. The inter-reticular distances d (002) for LP/KS, derived from X-ray diffraction patterns, are 3.57(1)/3.48(1) Å, with crystal thickness Lc (002) and graphitization degree of 1.4/2.0 nm and 6.9/13.1, respectively. Raman band deconvolution indicates graphitic domain sizes of L a = 6.7/8.2 nm and graphene-like flake tortuosity L t = 9.2/ 11.3 nm. Extensive density functional theory calculations on various 2D nanoflakes accurately predict that the D and G Raman bands may originate from graphene quantum dots, which form part of the nanostructure of these geomaterials. LP exhibits greater structural disorder than KS, along with a lower density (1.60 vs. 1.85 g/cm 3 ), suggesting a lower degree of graphitization, likely due to formation at a lower temperature (~300 • C). The Lopérec pyrobitumen is believed to result from a redox process involving a CO 2 -rich, oxidizing hydrothermal solution interacting with a local hydrocarbon source.</p></div>Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520

Source :

Harvested from HAL