علوم وتكنولوجيا

Permanent URI for this community

http://localhost:4000/handle/123456789/12888

Browse

Browsing علوم وتكنولوجيا by Author "Aida, M.S."

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Effect of copper doping on the photocatalytic activity of ZnO thin films prepared by solegel method
    (Elsevier, 2015) Saidani, T.; Zaabat, M.; Aida, M.S.; Boudine, B.
    In the present work, we prepared undoped and copper doped ZnO thin films by the sol egel dip coating method on glass substrates from zinc acetate dissolved in a solution of ethanol. The objective of our work is to study the effect of Cu doping with different concentrations on structural, morphological, optical properties and photocatalytic activity of ZnO thin films. For this purpose, we have used XRD to study the structural properties, and AFM to determine the morphology of the surface of the ZnO thin films. The optical properties and the photocatalytic degradation of the films were examined by UVevisibles spectrophotometer. The Tauc method was used to estimate the optical band gap. The XRD spectra indicated that the films have an hexagonal wurtzite structure, which gradually deteriorated with increasing Cu concentration. The results showed that the incorporation of Cu decreases the crystallite size. The AFM study showed that an increase of the concentration of Cu causes the decrease of the surface roughness, which passes from 20.2 for Un-doped ZnO to 12.16 nm for doped ZnO 5 wt% Cu. Optical measurements have shown that all the deposited films show good optical transmittance (77%e92%) in the visible region and increases the optical gap with increasing Cu concentration. The presence of copper from 1% to 5 wt% in the ZnO thin films is found to decelerate the photocatalytic process.
  • No Thumbnail Available
    Item
    Properties of (NiO)1-x(ZnO)x thin films deposited by spray pyrolysis
    (Springer, 2015) Herissi, L.; Hadjeris, L.; Aida, M.S.; Bougdira, J.
    Themain goal of the presentwork is the study of (NiO)1-x(ZnO)xmetal oxide thin films to determine their applicability in optoelectronic devices. For this purpose, well adherent films with x = 0, 0.25, 0.50, 0.75, and 1, were deposited by spray pyrolysis technique on glass substrates heated at 400 °C. Nickel chloride hexahydrate and zinc acetate dihydrate were used as precursors. Structural, electrical, optical and morphological properties of films have been studied. The obtained results indicate the formation ofNiO and ZnO phases mixed in defined proportions for intermediate compositions and the lattice constant of NiO increases with the nominal fraction x of Zn. The dark electrical conductivity at room temperature varied between 10−9 and 10−5 Ω cm−1. A transmittance in the visible region situated between 50% and 80% was observed. The band-gap changes of the samples are situated between 3.21 eV and 3.74 eV.