Abstract
Metal transition doped oxide thin films or nanocomposites have recently emerged at the forefront of potentials research. With the focus mainly on efficiency, the aspect of stability against optical irradiation of such materials has so far not been thoroughly addressed. This work covers the synthesis of silver doped lanthanum oxide thin films (La2O3:Ag) which have been prepared by the spray pyrolysis technique on glass substrates at 460°C. Then, Ag thin films were grown on lanthanum oxide thin films by thermal evaporation. The present work aims to reach the synthesis of La2O3:Ag thin films using both the spray pyrolysis and thermal evaporation techniques. First, X-ray diffraction analysis shows that undoped and Ag doped films crystallize in a mixture of hexagonal and cubic phase with crystallites oriented along (001) direction. Raman spectroscopy shows the bands positions corresponding to hexagonal and cubic phases. On the other hand, an attempt regarding their optical properties has been carried out by means of photoluminescence measurements. Second, from electrical conductivity measurements, the activation energy decreases from 1.42 to 1.09eV with the increase of annealing time and the charge carriers are following the CBH model as dominant charge transport mechanism. Finally, the annealing time influences the surface wettability property and transforms La2O3 character from hydrophobic (θ>90°) to hydrophilic (θ<90°).
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•Ag doped La2O3 thin films were successfully synthesized by spray pyrolysis at 500°C.•XRD study reveals that all the films are polycrystalline with spinel hexagonal and cubic structure.•PL intensity of La2O3: Ag films annealed in air for 1h and 2h is higher than that of pure La2O3.•The activation energy of the films decreases from 1.42 to 1.09eV with the different annealing time.•The transformation in the surface wettability property of La2O3 character from hydrophobic (θ>90°) to Hydrophilic (θ<90°).