## 3 Results and Discussion  
Typical \"cauliflower-like\" ZnO microparticles, prepared by the addition of ZnCl\({}_{2}\) to PDVB template microspheres under vacuum, followed by calcination of the obtained ZnCl\({}_{2}\)-PDVB composite microspheres in an air atmosphere, are presented in Figure 1.  
For all transmission electron microscopy (TEM) observation these \"Cauliflower-like\" ZnO microparticles were milled to smaller sized particles. Figure 2 is a representative TEM micrograph where a few nanoparticles can be discerned in a sample of milled \"Cauliflower-like\" ZnO microparticles. Both electron diffractions (insets A and B) show reflections that were found to belong to the hexagonal structure of ZnO (unit cell \(a\) = 3.25 A; \(c\) = 5.21 A pdf file # 01-0899-1397) Inset A is the selected area electron diffraction (SAED) taken from an area of 200 nm, displaying mainly a ring diffraction pattern. The reflections that appear in the SAED can be assigned to the {10.0}, {10.1}, {11.0} and {11.2} family of planes (in the hexagonal structure describing ZnO. The measured distances for these planes are 0.27 nm, 0.24 nm, 0.16 nm and 0.13 nm respectively. The reflection that appears in the nano beam electron diffraction (NBD, inset B) taken from a 4 nm area, as marked by the white arrow, shows clear sets of patterns. Analysis of one such pattern, (inset B) revealed sets of reflections that could be referred and indexed to the above mentioned structure of ZnO. The distances measured for the reflections were 0.16 nm, 0.1 nm and 0.078 nm matching, respectively, the interplanar spacings _d_\({}_{10.3}\), _d_\({}_{12.2}\) and _d_\({}_{21.5}\) family of planes. Figure 3 is a HRTEM image of a nanoparticle of ZnO, displaying well resolved lattice-fringe contrast and the identification was also based on the analysis of such high resolution images. Inset A represents the Fourier transform (FFT) of the portion of the image (white square) and looks like a diffraction pattern, geometrically identical to that which would be recorded in a diffraction experiment. Figure 1: “Cauliflower-like” ZnO microparticles: Scanning electron microscope (SEM) images of different magnifications. Analysis of this pattern revealed sets of reflections that could be readily referred to the hexagonal structure of (unit cell \(a=3.25\) A; \(c=5.21\) A pdf file # 01-0899-1397) and were successfully indexed. Inset B represents the processed and magnified portion of the image outlined by the white square. The distances measured between lattice fringes were 0.25 nm and 0.19 nm, matching the interplanar spacing for \(d_{10.1}\) and \(d_{10.2}\) family of planes. Using two different kinds of electron diffraction techniques (Figure 2 insets A and B) together with FFT analysis of the high resolution images, (Figure 3 inset A) showed that in this synthesis the crystalline hexagonal ZnO is formed. This result is also in good agreement with energy dispersive spectroscopy (EDS) elemental analysis (Figure 4) which shows that the elements Zn and O are in an atomic ratio of 43% and 57%, respectively. Those values conform (considering the precision limits of the EDS) to the atomic ratio in the compound ZnO. No carbon was detected in the EDS analysis, indicating that there are no residuals of the PDVB polymeric template in the obtained ZnO microparticles. The \"cauliflower-like\" ZnO microparticles were further characterized by fluorescence microscopy, and demonstrated fluorescence in the blue regions of the spectrum (Figure 5). **Figure 3.** High Resolution (HRTEM) electron micrograph of a nanoparticle resulting in this reaction. Inset (**A**) is the indexed Fourier Transform (FFT) taken from the area marked by the white square. The indexing corresponds to the hexagonal structure describing of ZnO. Inset (**B**) represents the magnified and processed portion of the image outlined by the white square, displaying the interplanar spacing for d\({}_{10.1}\) and d\({}_{10.2}\) family of planes.