**4. Conclusion**

*2D Materials*

**Table 1.**

**Figure 10.**

**14**

**Figure 11.**

G bands are shown in **Figure 11**.

*(a) D-band on left (Intensity: 33.5, Center: 1312.4 cm<sup>−</sup><sup>1</sup>*

The observed sub-micron size of the platelets obtained mentioned above, and imaged in **Figure 10**, was also verified via Raman spectroscopy, based on the use of Eq. (3) for the graphene nanoplatelets functionalized with Ammonia, whose D and

*for graphene nanoplatelets (ammonia) with 780 nm excitation and using fityk peak fitting software [14].*

*), (b) G-band on right (Intensity: 62.5, Center: 1580.2 cm<sup>−</sup><sup>1</sup>*

*)* 

*3D view of SEM data of functionalized graphene nanoplatelet aggregates doped with argon (A), carboxyl (B), oxygen (C), ammonia (D), fluorocarbon (E), and nitrogen (F), respectively, using Gwyddion software.*

**Element** *x* **average (μm)** *y* **average (μm)** *z* **average (μm)** Argon 4.8 3.9 0.50 Carboxyl 4.3 4.5 0.57 Oxygen 4.7 4.3 0.90 Ammonia 4.4 3.7 0.64 Fluorocarbon 5.0 3.6 0.55 Nitrogen 6.7 6.5 0.91

*Average x, y, z axis measurements of functionalized graphene nanoplatelet aggregates.*

To recap, in this chapter we have discussed the ability to discern whether certain graphitic nanomaterials are primarily 2 or 3 dimensional in character, based on features of their Raman bands. For all three materials (namely graphene, graphite, and functionalized graphene nanoplatelets), we have made use of Tuinstra and Koenig's relationship between the intensities of the D and G Raman bands to characterize the nanomaterials. In addition to the analysis based on Raman spectroscopy, SEM visualization/dimensional analysis was also performed on the graphene nanoplatelet samples. To conclude, the bulk macroscopic 3D character of graphite was clearly apparent compared to the 2D nature of graphene. However, based on the results for the graphene nanoplatelets, both 2D and 3D characteristics/behaviors were present for them, without one dimension dominating the other.

### **Acknowledgements**

Financial support from the National Science Foundation (Award# PHY-1358727 and PHY-1659224) is gratefully acknowledged.

#### **Conflict of interest**

No conflict of interest.

### **Author details**

Daniel Casimir, Hawazin Alghamdi, Iman Y. Ahmed, Raul Garcia-Sanchez and Prabhakar Misra\* Laser Spectroscopy Laboratory, Howard University, Washington, DC, USA

\*Address all correspondence to: pmisra@howard.edu

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
