3.3.3. FETEM and SAED Pattern Analyses

The FETEM image of *C. pentandra*/AgNO3 is shown in Figure 9a. This result showed that the *C. pentandra* fiber itself also can act as a reducing agent by donating the electron and hydrogen atom from the negatively charged functional groups in the cellulose of fiber. However, the FETEM image observed the big size and aggregation of Ag-NPs were formed. The particle size distribution histogram measured the average size of Ag-NPs incorporated in *C. pentandra* fiber is 37.86 nm as shown in Figure 9b. Figure 9c showed the results of the SAED pattern and lattice d-spacing of *C. pentandra*/AgNO3. The two rings around the SAED pattern at (111) and (311) is in line with the FCC plane of Ag-NPs of (111), (200), (220) and (222). Figure 9d showed the image of Ag-NPs with a latticed-spacing of ~0.14 nm correspond to the (220) cubic plane of Ag.

**Figure 9.** (**a**) Field Emission Transmission Electron Microscope (FETEM) image (**b**) particle size distribution histogram (**c**) SAED pattern and (**d**) lattice d-spacing parameter of *C. pentandra*/AgNO3.

However, after the addition of *E. spiralis* extract in the process of incorporation of Ag-NPs in *C. pentandra* fiber, the smaller size average size of Ag-NPs was observed as shown in Figure 10a. The shape of Ag-NPs is a spherical shape. The average size of Ag-NPs incorporated in *C. pentandra*/ Ag-NPs was decreased to 4.74 nm as shown in Figure 10b. The *E. spiralis* extract was introduced into the *C. pentandra* fiber to act as the reducing agent to reduce Ag<sup>+</sup> to Ag-NPs and also as stabilizing agent from its negatively charged functional groups in the *E. spiralis* extract. This result proved that the importance and novelty of using *E. spiralis* extract help to control the size, shape and stability of Ag-NPs with a simple technique, nontoxic and no additional of any chemical binding agent. Figure 10c,d showed the results of the SAED pattern and lattice d-spacing of *C. pentandra*/Ag-NPs, respectively. It clearly showed that the two rings around the SAED pattern at (200) and (222) are attributed to the FCC plane of Ag. This pattern is in line with the XRD pattern of the FCC plane of Ag-NPs of (111), (200), (220) and (222) of Ag-NPs. Figure 10c shows the image of *C. pentandra*/Ag-NPs with a latticed-spacing

of ~0.23 nm correspond to the (111) FCC plane of Ag. This plane is consistent with the appearance of the highest intensity of XRD peak at angle 38.48◦ (111) cubic plane of Ag as shown in Figure 8b.

**Figure 10.** (**a**) FETEM image (**b**) particle size distribution histogram (**c**) SAED pattern and (**d**) latticed-spacing parameter of *C. pentandra*/Ag-NPs.
