SILAR Synthesized CdO Thin Film for Ethanol Sensing

The effect of number of depositions on structural and gas sensing properties of CdO thin films prepared by low-costand effective successive ionic layer adsorption and reaction (SILAR) method. The structural, morphological and optical characterization of the deposited films were done using X-ray diffraction, SEM, TEM, UV-Vis spectroscopy etc. XRD patterns reveals that CdO thin film shows poly crystalline cubic cadmium oxide structure. The XRD analysis reports that crystallite size increases with number of deposition and also thickness increases.TEM shows particle size ~ 24-30 nm. SEM studies reveal increase in surface roughness and porosity with increase in thickness. Optical data shows band gap decreases with increase in thickness. Semiconducting metal oxides (SMO) are broadly used in gas sensors for sensing different gases. Their sensitivity can be increased by varying different parameters involved in deposition process. The gas sensing ability of CdO thin film shows that increasing of number of depositions enhances the sensitivity bizarrely for ethanol.