A study on the photoluminescence properties of electrospray deposited amorphous and crystalline nanostructured ZnO thin films

Transparent amorphous and crystalline nanostructured zinc oxide (ZnO) thin films were prepared by electrospray deposition technique on a glass substrate at 250 degrees C using zinc nitrate and ammonia as the precursors. The structural morphology and optical properties of the thin films were evaluated and also the effect of formation rate of basic generating species on the morphology of the thin films was discussed. Optical studies indicated that all of the thin films have a near band edge emission at 374 nm and a band gap of 3.32 eV. In addition, the films have an emission at 393 nm corresponding to ultra violet (UV) transmittance. However, the amorphous thin films have oxygen trap peak at 430 nm and two green transmittance peaks at 485 nm and 530 nm which are absent in the 0.1 molar nanostructured sample. The crystallite size of the thin films which calculated from XRD patterns via Debye-Scherrer's formula was around 30 nm. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.