Graphene Nanocomposites Studied by Raman Spectroscopy

Abstract

The goal of this chapter is to provide a general introduction about graphene nanocomposites studied by Raman spectroscopy. The chapter will therefore begin with a brief description of the major Raman bands of carbon allotropes. In the following chapter a concise comparison between single walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), fullerenes and graphene is exposed. The characteristic features in Raman spectra of carbon allotropes, namely the intense signals D and G are investigated. In particular, the chapter will outline the Raman spectrum of graphene and different types of graphene oxide. The last part of the chapter is devoted to graphene nanocomposites.

Enhanced Thermal Conductivity of Polyamide-Based Nanocomposites Containing Graphene Oxide Sheets Decorated with Compatible Polymer Brushes

“…In fact, intensity of the Raman bands in the spectrum of PA6/GO_PAAM is much higher than that observed for PA6/GO, for which the band intensity is only slightly higher than the noise level, in spite of a similar content of GO for both samples. This can be explained by the formation of clusters of GO in PA6/GO, which leads to a decrease in the band intensity, as observed previously [40][41][42].…”

Modification of Graphene Oxide/V2O5·nH2O Nanocomposite Films via Direct Laser Irradiation

“…The deconvoluted components of GO/V 2 O 5 · n H 2 O and rGO/V 2 O 5 · n H 2 O (LPD of 2.71 × 10 5 W/cm 2 ) in XPS O 1s spectra were assigned to V–O linkage in the V 2 O 5 (530.15 and 530.24 eV), O–C=O (531.35 and 531.33 eV), C–O (532.21 and 532.25 eV), and O–H (532.94 and 533.08 eV) chemical bonds. 62 , 70 , 72 The intensity decrease of C–O component at 532.25 eV for rGO/V 2 O 5 · n H 2 O ( Figure 4 a 2 ) indicates the removal of carbon–oxygen bounds. The additional component of GO/V 2 O 5 · n H 2 O and rGO/V 2 O 5 · n H 2 O observed in XPS O 1s spectra at 534.09 and 534.18 eV is related to water molecules.…”

“…The second order overtone, 2D, is due to the two-phonon double resonance, while the D+G band is attributed to higher structure disorder of GO. 70 …”

Synthesis and Characterization of Electrospun Composite Scaffolds Based on Chitosan-Carboxylated Graphene Oxide with Potential Biomedical Applications

“…In the case of the CS/PG 0.1% scaffold, the broad shape of the 2D band suggests the existence of multiple GO-COOH layers stacked into the polymer matrix. On the contrary, the presence of a sharper 2D band from the CS/PG 0.2% composite spectrum indicates a better exfoliation of GO-COOH agglomerates [ 52 ] due to the multiple interactions between PEO (-O-) and CS (-OH, -NH 2 ) functionalities and -COOH groups of GO-COOH sheets enhancing the distance between GO sheets. The more pronounced (D + G) combination peak in the spectra of CS/PG 0.1% and CS/PG 0.5% supports the presence of intercalated structures compared to CS/PG 0.2% due to the stacking tendency of GO-COOH layers.…”