Optical Properties of ZnO Nanoparticles Synthesised from a Polysaccharide and ZnCl₂

In this article we study the optical properties of ZnO nanoparticles. This paper describes cost effective, high yield, and a facile synthetic method for the synthesis of ZnO nanoparticles from precursors viz. linear polysaccharide, chitosan, and ZnCl₂ by a precipitation method. The synthesized ZnO nanoparticles were characterized by surface area, pore size, and UV-visible measurements. The optical band gap and the Urbach energy were also calculated and the optical band gap energy of the synthesized ZnO nanoparticles was found to be 3.26 eV and the nature of the optical transition has been identified as direct allowed.