Fig. 3. TEM images of the Ag NPs/CS-Starch bio-composite.
Chemical constitution of the Ag NPs/CS-Starch nanocomposite was assessed by EDX analysis and the corresponding output is presented in Fig. 4. It clearly shows Au and Ag as the two metallic components along with some other peaks of C, N and O as the non-metals. A major signal of Au is observed at 2.1 KeV, which however not coming from the sample, but attributed to the gold vapor deposition prior to sample analysis. Another signal of Ag is found at 2.95 keV. The non-metal signals correspond to the associated CS-Starch composite. The map sum spectrum, being studied from the EDX profile evidently tells the major constituent of the composite being carbon (75.2 wt%). Ag occupies as 8.5 wt % of the total composite. The EDX data was further emphasized by elemental mapping analysis. On X-ray scanning of a section of FE-SEM image, the elemental constitution map or location can be detected. As can be seen from Fig. 5, the output displays a homogeneous distribution of constitutional elements over the surface. This is very important for the biocomposite for superior performance towards its applications.