Raman spectroscopy and imaging of Bernalstacked bilayer graphene synthesized on copper foil by chemical vapour deposition: growth dependence on temperature
dc.contributor.author | Fabiane, M. | |
dc.contributor.author | Madito, M. J. | |
dc.contributor.author | Bello, A. | |
dc.contributor.author | Manyala, N. | |
dc.date.accessioned | 2017-02-01T09:11:12Z | |
dc.date.available | 2017-02-01T09:11:12Z | |
dc.date.issued | 2017 | |
dc.description.abstract | We report on the effect of temperature on the growth of bilayer graphene on a copper foil under atmospheric pressure chemical vapour deposition (AP-CVD). Before characterization of the AP-CVD bilayer graphene, a high-quality graphene flake was obtained from the Kish bulk graphite by micro-mechanical exfoliation and characterized by using Raman spectroscopy and imaging. The Raman data of the exfoliated, high-quality graphene flake show monolayer and bilayer graphenes and were compared with the Raman data of AP-CVD graphene. Raman spectroscopy of AP-CVD graphene shows bilayer films that exhibit predominantly Bernal stacking with an I2D/IG ratio of ~1. At low growth temperature (~780 °C), Raman disorder-related peak intensity in the AP-CVD graphene is high and decreases with an increase in growth temperature to the lowest disorder intensity at ~973 °C. The selected area electron diffraction and atomic force microscopy average step height analysis showed the thickness of the bilayer graphene. The AP-CVD graphene is uniform at low growth temperatures (~780 °C) with a high disorder and becomes nonuniform at high growth temperatures (~867–973 °C) with a very low disorder as bilayer graphene evolves to form islands with an average lateral size of <10 μm. Competition between carbon adatoms supply through dehydrogenation of the CHx species, mobility and desorption rate of the carbon-adatom species for nucleation of the bilayer graphene as a function of temperature is elucidated. This study provides further insight into the growth mechanisms of bilayer graphene by AP-CVD on Cu. | en_ZA |
dc.identifier.issn | 1097-4555 | |
dc.identifier.uri | http://dx.doi.org/10.1002/jrs.5094 | |
dc.identifier.uri | http://repository.tml.nul.ls/handle/20.500.14155/1151 | |
dc.language.iso | en | en_ZA |
dc.rights | Copyright © 2017 John Wiley & Sons, Ltd. | en_ZA |
dc.source | Journal of Raman Spectroscopy | en_ZA |
dc.subject | graphene | en_ZA |
dc.subject | AP-CVD | en_ZA |
dc.subject | copper foil | en_ZA |
dc.subject | Bernal-stacked bilayer | en_ZA |
dc.subject | exfoliated graphene | en_ZA |
dc.title | Raman spectroscopy and imaging of Bernalstacked bilayer graphene synthesized on copper foil by chemical vapour deposition: growth dependence on temperature | en_ZA |
dc.type | Article | en_ZA |