Effect of oxygen partial pressure on the microstructural, optical and gas sensing characterization of nanostructured Gd doped ceria thin films deposited by pulsed laser deposition

Microstructural properties of 10 mol% gadolinium doped ceria (CeO2) thin films that were deposited on quartz substrate at substrate temperature of 1023 K by using pulsed laser deposition with different oxygen partial pressures in the range of 50-200 mTorr. The influence of oxygen partial pressure on microstructural, morphological, optical and gas sensing characterization of the thin films was systematically studied. The microstructure of the thin films was investigated using X-ray diffraction, atomic force microscopy and Raman spectroscopy. Morphological studies have been carried out using scanning electron microscope. The experimental results confirmed that the films were polycrystalline in nature with cubic fluorite structure. Optical properties of the thin films were examined using UV-vis spectrophotometer. The optical band gap calculated from Tauc's relation. Gas sensing characterization has been carried at different operating temperatures (room temperature to 523 K) for acetone gas. Response and recovery times of the sensor were calculated using transient response plot.