**2. Experimental**

**Figure 4** shows the primary instrument used to record most of the Raman spectra; it was a DXR SmartRaman spectrometer from Thermoelectron (that uses 780, 532, and 455 nm laser sources). The first wavelength (780 nm) was used for the bulk of the recorded spectra and utilized a high brightness laser of the single mode diode (as does the 532 nm light source), while the 455 nm source is a diode-pumped solid-state laser. Using the 180° geometry, after focusing the laser beam on the sample, the backscattered radiation from the sample enters the spectrometer via a collection lens, and the Stokes-shifted Raman spectrum was recorded as read by the CCD detector using the correct Rayleigh filter and automated entrance slit selections. A full range grating was used with the triplet spectrograph.

**11**

**Figure 5.**

**Figure 6.**

*Raman Spectroscopy of Graphene, Graphite and Graphene Nanoplatelets*

*InVia Raman spectrometer schematic and instrument image from the Renishaw manual.*

The Renishaw inVia Raman spectrometer (**Figure 5**) uses a 532-nm laser source and was employed to record the Raman spectra of CVD graphene and the functionalized graphene nanoplatelets. It consists of a microscope to shine light on the sample and collecting the scattered light, after filtering all the light except for the tiny fraction that has been Raman scattered, together with a diffraction grating for splitting the Raman scattered light into its component wavelengths, and a CCD

Graphene nanoplatelets (GNP) are usually produced by the intercalation of graphite through various means, followed by an acid purification process, and further exfoliation of the initial GNP flakes [9]. Besides intercalation, irradiation with microwaves, or extreme heating is also sometimes used to produce GNP from

Images of functionalized graphene nanoplatelets were taken with the JEOL JSM-7600F scanning electron microscope (SEM) shown in **Figure 6**. The secondary electron detector on the SEM uses an EMI current of 138.20 nA. Beam current employed had a range of 1 pA to 200 nA. The JEOL JSM-7600F SEM contains a large variety of detectors that can be used on specimen samples up to 200 mm in diameter. Various magnifications were selected when appropriate to accurately

camera for final detection of the Raman spectrum.

*Two views of the JEOL JSM-7600F scanning electron microscope (SEM) setup.*

the host graphite source [10].

*DOI: http://dx.doi.org/10.5772/intechopen.84527*

**Figure 4.** *DXR SmartRaman spectrometer (left) and DXR schematic (right).*

*Raman Spectroscopy of Graphene, Graphite and Graphene Nanoplatelets DOI: http://dx.doi.org/10.5772/intechopen.84527*

#### **Figure 5.**

*2D Materials*

per unit wave-vector k.

**2. Experimental**

**Figure 3.**

The 2D nature of graphene plays a direct role in this result, sine g(E), which gives the number of available states within the energy interval E and E + dE, is defined in two-dimensions in terms of the ratio of an element of area dA in k-space

*Graphene's reciprocal space lattice shown with reciprocal lattice vectors b1, and b2. The first Brillouin zone is* 

*the region labeled by Γ. Also shown are the six high symmetry regions, Γ, K, M, and K′.*

**Figure 4** shows the primary instrument used to record most of the Raman spectra; it was a DXR SmartRaman spectrometer from Thermoelectron (that uses 780, 532, and 455 nm laser sources). The first wavelength (780 nm) was used for the bulk of the recorded spectra and utilized a high brightness laser of the single mode diode (as does the 532 nm light source), while the 455 nm source is a diode-pumped solid-state laser. Using the 180° geometry, after focusing the laser beam on the sample, the backscattered radiation from the sample enters the spectrometer via a collection lens, and the Stokes-shifted Raman spectrum was recorded as read by the CCD detector using the correct Rayleigh filter and automated entrance slit selec-

tions. A full range grating was used with the triplet spectrograph.

*DXR SmartRaman spectrometer (left) and DXR schematic (right).*

**10**

**Figure 4.**

*InVia Raman spectrometer schematic and instrument image from the Renishaw manual.*

**Figure 6.** *Two views of the JEOL JSM-7600F scanning electron microscope (SEM) setup.*

The Renishaw inVia Raman spectrometer (**Figure 5**) uses a 532-nm laser source and was employed to record the Raman spectra of CVD graphene and the functionalized graphene nanoplatelets. It consists of a microscope to shine light on the sample and collecting the scattered light, after filtering all the light except for the tiny fraction that has been Raman scattered, together with a diffraction grating for splitting the Raman scattered light into its component wavelengths, and a CCD camera for final detection of the Raman spectrum.

Graphene nanoplatelets (GNP) are usually produced by the intercalation of graphite through various means, followed by an acid purification process, and further exfoliation of the initial GNP flakes [9]. Besides intercalation, irradiation with microwaves, or extreme heating is also sometimes used to produce GNP from the host graphite source [10].

Images of functionalized graphene nanoplatelets were taken with the JEOL JSM-7600F scanning electron microscope (SEM) shown in **Figure 6**. The secondary electron detector on the SEM uses an EMI current of 138.20 nA. Beam current employed had a range of 1 pA to 200 nA. The JEOL JSM-7600F SEM contains a large variety of detectors that can be used on specimen samples up to 200 mm in diameter. Various magnifications were selected when appropriate to accurately

display sample structure; SEM magnification ranges between 25 and 1,000,000×. The modular software program Gwyddion was used to generate three-dimensional visualization of the nanoplatelet aggregate structures.
