Synthesis of ZnO nanoparticles without catalysts and their photoluminescence

In this paper, we demonstrate a novel and direct synthesis of high quality zinc oxide (ZnO) nanoparticles by a versatile and a simple approach without using catalysts. The approach is based on a simple reaction of zinc powder and de-ionized (DI) water at relatively low temperatures of 200 degrees C. The formation of ZnO nanoparticles by the reaction of metals with DI water is suggested to occur due to the oxidation of metallic zinc in presence of water. The nanoparticles have diameters varying between 50 to 90nm, with an average diameter of 70 nm. The synthesized ZnO products were characterized in terms of their structural and optical properties. Photoluminescence (PI) measurements were adopted to analyze the optical properties of nanoparticles; both a strong UV emission and weak deep level emissions were observed. The reported method besides being catalyst free is economical, fast, environmentally benign and free of pollution, which will make it suitable for large scale production.