## 3 Results and Discussion
### X-ray Diffraction  
Figure 6 shows the XRD pattern of the synthesized graphene oxide and the GO/Zn(OH)x nanocomposite materials (A). The diffraction pattern of the synthesized graphene oxide shows a typical diffraction pattern of GO. The expansion of the graphite lattice along the c-axis causes the graphite 002 peak to shift and become the GO 001 peak located at 11.68 in 20 [56; 57]. This is a consequence of the oxidation of the surface of the layers in the graphite, which caused expansion of the c-axis in the crystal (the 002 plane in graphite); as the expansion is large, the 002 peak moves lower in diffraction angle, which indicates an increase in the interplanar graphite spacing and for some reason, it is named the 001 peak [57; 58; 59].  
Figure 6B shows the Le Bail fitting of the graphene oxide sample, which shows a good agreement between the literature and the fitting results, as indicated by the low \(\chi^{2}\) value in Table 2 of 1.13. Also, there is evidence of the presence of some residual graphite in the sample after synthesis, as is evidenced by the small peak at 31.26 in 20 [53]. It can be seen in Figure 6B that the synthesized GO/Zn (OH)x composite materials exhibit a diffraction pattern consisting of numerous peaks. The composition of the GO/Zn (OH)x composite samples was determined to be a combination of three components, which were graphene oxide, \(\epsilon\)-Zn (OH)2, and Zn5(OH)10 2H2O. In addition, it should be noted that the GO peak has shifted to a slightly higher diffraction angle, which indicates a slight compression in the length of the C-axis. The compression of the C-axis of the crystal is also evidenced by the small shift in the diffraction pattern for the GO 001 peak from 11.68 to 12.78 \({}^{\circ}\) in 20. This change in the diffraction angle indicates a 0.4 A decrease in the interplanar spacing of the graphene oxide. This compression of the structure may be due to the removal of smaller pieces of graphene oxide after the reaction with the Zn\({}^{2+}\) and the OH\({}^{-}\) ions in the solution. Alternatively, it may be caused by the fact that some of the groups changed after the reaction, causing the planes to come closer together.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Sample** & **Element (Shell)** & **Weight (\%)** & **Atomic (\%)** & **Net Int.** & **Error (\%)** & **Kratio** & **Z** & **A** & **F** \\ \hline GO & C(K) & 58.24 & 65.01 & 637.70 & 3.86 & 0.48 & 1.02 & 0.81 & 1.00 \\ \hline  & O (K) & 41.76 & 34.99 & 351.20 & 7.88 & 0.17 & 0.97 &  
The composition was determined using the Le Bail fitting procedure in the Fullprof software (Version 5.10) and crystallographic data from the literature [60]. The Le Bail fitting of the GO/Zn (OH)\({}_{\chi-75}\) is shown in Figure 6C and the results of the fitting are presented in Table 2. The Le Bail fitting had a \(\chi^{2}\) of 2.03, which indicates a good agreement between the literature values and the experimental data [26; 59; 61; 62]. The lattice values are also within a reasonable error of the literature crystal structures.  
Figure 6: **(A)** XRD diffraction of GO and and GO/Zn (OH)\({}_{\chi}\) composites; (**B**) Le Bail fitting of the diffraction pattern collected for the GO sample; (**C**) Le Bail fitting of the diffraction pattern for the GO/Zn (OH)\({}_{\chi}\) 75 wt.% sample.