Pulsed Galvanostatic Synthesis of Zinc Oxide Nanostructures

In the present paper, various nanostructures of zinc oxide are prepared by the pulse current electrochemical technique on the zinc substrate in sodium sulfide solution as a pH adjuster. To achieve homogenous morphology, smallest size distribution, and the best composition of sample, the impacts of experimental variables including sodium sulfide concentration, type and concentration of additives, pH, bath temperature, frequency and height of the pulse (current density) have been evaluated. The synthesized nanoparticles have been carefully characterized using several techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), and X-ray diffraction (XRD). The results revealed that the morphology and particle size of ZnO samples depends strongly on the amounts of synthesis parameters. The ZnO sample synthesized in 62.5 mA. cm(-2) density of current, pulse and relaxation time of 1 s, mixing rate of 200 rpm, 0.001 M Na2S, solution pH of 12.7, and electrocrystallization temperature of 45 degrees C, 5 g/l PVP as manager of structure additive includes uniform ZnO nanoparticles with 30 nm average diameter. When the synthesis solution is at a standstill and the CMT is zero, ZnO sample includes uniform nanosheets with average thickness lower than 30 nm. According to the results, the pulsed galavanostatic technique can be used as a valid and controllable method to synthesize the zinc oxide nanoparticles.