Synthesis and study of ZnO nanoparticles by polymer pyrolysis route using two different polymerization initiators

Ammonium persulfate (APS) and sonochemical (SON) as different polymerization initiators were used to obtain ZnO polyacrylate salt via an intermediate stabilized step for the synthesization of zinc oxide nanocrystals (nc-ZnO). Impurity-free nc-ZnO with wurtzite structure was obtained, after calcinating both synthesized ZnO polyacrylic salts. The way by which the polymerization initiation was done greatly affect the morphological nature, shape, and size, of both synthesized samples. The obtained particle size values of the sample range from 15 to 45nm when using APS (S1) and range from 58 to 120nm when using sonochemical (S2). This difference in the range of particle size for both samples was reflected on the respective values of their optical energy gaps that found to be 3.33 and 3.26eV for S1 and S2, respectively. The intensities and shift of the visible emissions of photoluminescence (PL) spectra showed strong correlation with the particle size of both considered samples. The photocatalytic activities (PCA) of the synthesized samples were tested using UV-VIS irradiation for methyl orange (MO), where the difference in PCA for both samples was discussed in view of their PL spectra as well as their microstructure and morphology features.