Physical properties of mixed TiO2-CdO thin films for gas sensor applications

Abstract

TiO2-CdO thin films were grown by Nd: YAG pulsed laser deposition (PLD) at different laser energies of (500-900) mJ. According to the findings of the XRD analysis, each film possessed a cubic polycrystalline crystal structure with a predominant peak along the (111) plane. The average crystallite size was corrected using Warren-Scherrer's corrections, and their values were found to lie between (12.23 and 83.40) nm. The AFM images indicate that the average particle size reduced as the laser energy increased, while surface roughness and root mean square values were raised as the laser energy increased. Optical properties showed that the bandgap decreases from 2.09- 1.8 eV with increasing laser energy. The increment in laser energy results in a rise in particle size and the average roughness. The maximum Sensitivity of TiO2-CdO films towards H2 gas was 72.3%, and the response time was within 24– 67.9 sec.