Figure 2

X-ray diffraction θ-2θ scans of powder samples of various sizes of ZnO nanoparticles recorded in air at room temperature. The X-ray source used was Cu K_αwith an effective wavelengthλ = 1.5418 Å. The peak widths are inversely related to the crystallite sizes according to the Scherrer relation, enabling the XRD patterns to demonstrate the change in particle size. The stick pattern from reference data for wurtzite ZnO is shown along thex-axis (represented by thesolid squares) and fully indexes the experimental data. Theinset shows the relationship between average crystallite size (L) and average aspect ratio (AR) of several samples, prepared using the synthesis method employed in this work, as determined by XRD. AR was calculated from the widths of the (100) and (002) XRD peaks, and excludes data for 4-nm samples due to the amount of peak overlap