**6. Conclusion**

**5.3. SEM-Z contrast-STEM combined experiments**

**Figure 24.** Graphene images in (a) SEM mode; (b) Z-contrast mode; (c) STEM mode.

*different modes on the same sample location*.

**5.4. HR-STEM experiments**

**Figure 25.** Graphene: (a) HR-STEM image (b) FFT image.

**5.5. Nano-diffraction experiments**

of graphene (nicely hexagonally shape).

line planes.

The special features of the synthesized graphene are presented in **Figure 24** based on the capabilities of the special equipment presented above: *graphene images in SEM mode, Z contrast and STEM modes at the same sample location*. In these amazing images the SEM mode image suggest two graphene sheets one top of the other. This is confirmed by STEM image, since the top part is black denoting thicker structure. On the other hand the Z contrast image is showing only the presence of carbon in the sample. *This is one of the great advantages to have images in*

306 Applications of Laser Ablation - Thin Film Deposition, Nanomaterial Synthesis and Surface Modification

**Figure 25(a)** is a very good quality HR-STEM image of graphene sheet. We can observe the carbon atoms and their periodically disposal into lattice. Also we performed fast Fourier transform (FFT) and as can be seen in **Figure 25(b)** we identified two directions with crystal-

To confirm the presence of graphene in our product we performed electron nano-diffraction measurement. We can see in **Figure 26** that the diffraction pattern is confirming the presence The present work highlighted the important specific synthesis way of carbon based nanomaterials, especially SWCNTs, and described the most used production routes using laser ablation technique.

We proved by micro-Raman spectroscopy, AFM, SEM, TEM, HR-TEM, STEM, HR-STEM, SEM-STEM, and TGA that high quality of carbon nanomaterials have been synthesized via laser ablation technique in ours laboratories.

Tuning experimental parameters we demonstrate how to switch to different type of synthesized carbon nanomaterials, i.e., SWCNTs, CNOs, and graphene.

We show for the first time images of *SWCNTs in SEM, Z contrast, TEM, and EDX modes at the same sample location* leading to the identification of SWCNTs, catalyst grains and amorphous carbon.
