Raman modes in transferred bilayer CVD graphene

Abstract

Abstract:A systematic experimental Raman spectroscopic study of twisted bilayer graphene (tBLG) domains localized inside wide-area single layer graphene (SLG) produced by low-pressure CVD on Cu foil and transferred onto SiO /Si substrate has been performed. According to the Raman characterization the tBLG domains had a great variety of twisting angles θ between the bottom and top graphene layers (

Discontinuity and misorientation of graphene grown on nickel foil: Effect of the substrate crystallographic orientation

“…These modes are specific to the AB-stacked graphene [50][51][52]. In addition, the Raman features in the range of 80-130 cm À1 corresponded to the ZO 0 breathing modes, and facilitated by rotational disorder [53,54], are missing (left inset, Fig. 7a).…”

“…7b), in the spectral region of the ZO 0 breathing modes, a structure exists, which can be divided into three Lorentzian-shape bands (at 107, 115 and 122 cm À1 ) of several rotated graphene layers in MLG. The ZO breathing mode is characterized by the Raman peak at approximately 800 cm À1 [66], and its exact position has a tight relationship to the spectral position of the rotation mode R and therefore to the rotation angle h [54]. On the high background, due to the Ni substrate, some very weak peculiarities in this region were detected including a broadened structure below 800 cm À1 and peaks at 820 and 841 cm À1 (lower right inset, Fig.…”

“…The corresponding rotation angles (h) were estimated to be approximately 26°and 13°, respectively, based on the x R = x R (h) relationship. In the spectral range of 80-130 cm À1 belonging to the ZO 0 breathing modes [53,54] several overlapping Lorentzian peaks were observed. The most intense peaks of them are located at 106, 115 and 121 cm À1 , which indicate the presence of several rotated graphene layers that have slightly different breathing frequencies.…”

Composite 2D Nanointerfaces for Electrochemical Biosensing: An Experimental and Theoretical Study

“…Raman spectroscopy is the definitive characterization technique for the confirmation of the presence of sp 2hybridized graphitic carbon in a sample. 46 Two prominent peaks are observed in the Raman spectrum in Figure 1c, namely, the G-band at 1595.85 cm −1 and the D-band at 1360.59 cm −1 . The G-band is attributed to bond stretching of sp 2 carbon atoms in both aromatic and aliphatic compounds while the D-band is attributed to lattice defects in the graphitic plane.…”

“…Figure c is the Raman spectrum for the as-synthesized graphene material. Raman spectroscopy is the definitive characterization technique for the confirmation of the presence of sp 2 -hybridized graphitic carbon in a sample . Two prominent peaks are observed in the Raman spectrum in Figure c, namely, the G-band at 1595.85 cm –1 and the D-band at 1360.59 cm –1 .…”