Structural, morphological and optical studies of various substrate temperatures of ZnO thin films by spray pyrolysis

Abstract

We report the synthesis and characterisation of ZnO by using Spray pyrolysis method. The synthesized ZnO thin films of various substrate temperatures (300 °C, 350 °C, 400 °C and 450 °C) have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX), and UV-Visible spectroscopy. The crystal structures of ZnO have been confirmed with crystallite sizes 15.65nm-32.91 nm, the dislocation density, microstrain decreasesed, interplanar distance also decreased from 2.159 to 1.942 for 300 °C to 450 °C of substrate temperatures using XRD data. The nanoparticles (NPs) grain size increase from 48.3 nm to 151.8nm by increasing substrate temperature morphologies of ZnO have been observed by using FESEM. The elemental compositions have been investigated using EDX. The optical band gap for ZnO has been estimated that on increasing substrate temperatures (300 °C, 350 °C, 400 °C and 450 °C) is decreased (3.203eV to 3.045eV) from UV-Visible analysis data.