Nanostructured Al and Fe co-doped ZnO thin films for enhanced ammonia detection

Abstract

Pure and Al, Fe doped/co-doped zinc oxide (ZnO) thin films were prepared using spray pyrolysis technique with optimised deposition parameters. Micro-structural properties of the films were carried out using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy. XRD results have shown that the deposited thin films were polycrystalline in nature with Wurtize structure. Crystallite size was determined and it was found to be decreased with single dopants and increased while co-doping in the zinc oxide matrix. Morphological studies have been studied by using Atomic Force Microscopy and Field Emission Scanning Electron Microscopy. They have clearly shown that the deposited thin films are agglomerated spherical particles with uniform distribution. Optical properties of the films were measured by UV–Vis spectrophotometer. Optical band gap was determined using Touc plot. Gas sensing characterization of pure and doped/co-doped ZnO thin films were carried out at room temperature in static liquid distribution method towards different gases such as acetone, ethanol, xylene and ammonia. Response and recovery times were also calculated and reported.