Room Temperature Synthesis of Monodisperse ZnO Nanoparticles Using Ultrasonically Atomized Precursor Mist in Simple Chemical Route

Abstract

Monodisperse zinc oxide (ZnO) nanoparticles were synthesized using ultrasonically atomized precursor mist in simple chemical route at low temperature. Analytical grade sodium hydroxide and zinc chloride were dissolved in 100 ml methanol. Zinc chloride precursor solution was converted into very fine mist (atomized) using a nozzle (Sono-Tek Corporation, U.S.A.) operated at ultrasonic frequency of 120 KHz. Fine mist droplets were added slowly (50ml/ hour) into sodium hydroxide solution in 2 hours. The NaOH solution in beaker turned slowly into white product due to addition of zinc chloride. The white product was kept in constant temperature bath at 90°C for 3 hours. The white product was washed five times using double distill water and dried in oven for 2 hours. Different powder samples were synthesized using same procedure by changing the molarity of sodium hydroxide keeping the molarity of zinc chloride and other preparative conditions same. The structural, microstructural, thermal and optical properties of fine powders were analyzed using X Ray Diffractometer, Scanning Electron Microscopy, Simultaneous Thermal Analyzer, UV-Vis Spectroscopy and Photoluminescence Spectroscopy. Fine ZnO nanorods, elongated and spherical nanoparticles were observed due to change in molarity of NaOH. The results are discussed and interpreted.