Analyzing the Raman Spectra of Graphenic Carbon Materials from Kerogens to Nanotubes: What Type of Information Can Be Extracted from Defect Bands?

Abstract

Considering typical spectra of a broad range of carbonaceous materials from gas-shale to nanotubes, various ways by which defects show up in Raman spectra are exampled and discussed. The position, resonance behavior, and linewidth of both the D and G bands are compared, even if in some cases obtaining accurate information on the materials from the fitting parameters is a difficult task. As a matter of fact, even if a full picture is unreachable, defining parameter trends is one acceptable option. Two ways to determine the linewidth, either graphically and or by fitting are proposed in order to be able to compare literature data. The relationship between the crystallite size obtained from the linewidth and from X-ray diffraction, which is complementary to the Tuinstra and Koenig law, is examined. We show that a single approach is not possible unless modeling is performed and therefore that analysis of Raman spectra should be adapted to the specificities of each sample series, i.e., a minimum of knowledge about the materials is always required.

Influence and Electrochemical Stability of Oxygen Groups and Edge Sites in Vanadium Redox Reactions

“…The ratios of our samples are between 2.56 (GF/CNT) and 2.91 (GF/CNT/KOH), which is why we characterize the defects on our samples as edge site like. Due to a ratio <3.5, we have multiple edge sites in a so‐called loop configuration [41] …”

Graphene Domain Signature of Raman Spectra of sp2 Amorphous Carbons

“…This format has legitimated the use of RSs parameters, such as position, bandwidth and intensity of the D, G, and 2D bands (particularly, largely exploited parameters , and ) for the determination of the confinement parameters, thus characterizing the carbon crystals nanostructuring (see a number of cases in [ 1 ] and references therein). The same standard appearance of the RSs of crystalline and non-crystalline graphene-based solids stimulated expansion of the phonon-confinement approach to amorphous carbons, graphene quantum dot, and other non-crystalline species (see [ 13 , 14 , 15 , 16 ]), thus presenting the latter now as the main stream in the consideration of the RSs of all graphene-based carbons “proposed by international consensus” [ 1 ].…”

In Vitro Hyperthermia Evaluation of Electrospun Polymer Composite Fibers Loaded with Reduced Graphene Oxide

“…Additionally, a very small D band is observed at 1350 cm −1 , which is typically associated to the breathing modes of aromatic carbon rings. This band is attributed to the edge defect and functional groups present in the lattice of graphene materials [ 28 , 29 ]. The 2D band, which is the overtone of D bands is seen ca.…”