Surface-enhanced Raman spectra on graphene

0484439 - ÚFCH JH 2019 RIV GB eng J - Journal Article
Ek Weis, Johan - Vejpravová, Jana - Verhagen, Timotheus - Melníková, Zuzana - da Costa, Sara - Kalbáč, Martin
Surface-enhanced Raman spectra on graphene.
Journal of Raman Spectroscopy. Roč. 49, č. 1 (2018), s. 168-173. ISSN 0377-0486. E-ISSN 1097-4555
R&D Projects: GA MŠMT LL1301; GA ČR(CZ) GA15-01953S; GA MŠMT(CZ) LM2015073; GA MŠMT(CZ) EF16_013/0001821
Institutional support: RVO:61388955 ; RVO:68378271
Keywords : charge transfer * graphene * graphene-plasmon interaction
OECD category: Physical chemistry; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D)
Impact factor: 2.809, year: 2018

Surface-enhanced Raman spectroscopy is a valuable tool for inspection of trace concentrations of various molecules. Hence, this method has a great potential for characterization of functionalised graphene. However, to make this method a reliable analytical tool, the influence of the metal–graphene interactions on Raman spectra of the graphene must be understood. Here, the surface-enhanced Raman spectra of exfoliated single-layer graphene covered with gold or silver thin layers were studied. The metal–graphene interactions resulted in the broadening of the G mode and the 2D mode of graphene. A change of the 2D mode dispersion was also observed. The effects were found to be weaker for the silver layer. However, the Raman signal enhancement of the graphene features was found to be significantly stronger in case of the silver layer. Various scenarios of the observed effects are discussed: graphene–plasmon interaction, charge transfer between the metal and graphene, and selective enhancement at the lattice and topographic defects.
Permanent Link: http://hdl.handle.net/11104/0279605