Raman spectroscopy of graphene at high pressure: substrate and pressure transmitting media effects

K. Filintoglou; N. Papadopoulos; J. Arvanitidis; D. Christofilos; O. Frank; M. Kalbac; J. Parthenios; G. Kalosakas; C. Galiotis; K. Papagelis

arXiv · 1304.8040

Raman spectroscopy of graphene at high pressure: substrate and pressure transmitting media effects

K. Filintoglou·N. Papadopoulos·J. Arvanitidis·D. Christofilos·O. Frank·M. Kalbac·J. Parthenios·G. Kalosakas·C. Galiotis·K. Papagelis

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Abstract

The pressure evolution of the Raman spectrum of graphene grown by chemical vapour deposition on polycrystalline copper is investigated with the use of a polar and a non-polar pressure transmitting medium (PTM). The G and 2D Raman bands exhibit similar pressure slopes for both PTM irrespectively of any unintentional initial doping and/or strain of the samples. Our analysis suggests that any pressure-induced charge transfer effects are negligibly small to influence the pressure response of graphene. This is determined by the mechanical stress due to the pressure-induced substrate contraction and the transfer efficiency of the latter to the graphene layer, as well as the PTM-graphene interaction. For the non-polar PTM, a peculiar pressure behavior of graphene is observed in the PTM solidification regime, resembling that of free standing graphene.

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K. Filintoglou, N. Papadopoulos, J. Arvanitidis, D. Christofilos, O. Frank, M. Kalbac, J. Parthenios, G. Kalosakas, C. Galiotis, K. Papagelis. 2013-04-30. Raman spectroscopy of graphene at high pressure: substrate and pressure transmitting media effects. https://arxiv.org/abs/1304.8040

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