Résumé:
Elaboration and characterization of composite materials based on nanoparticles of the semiconductor CuO and the rare earth oxide Dy2O3 dispersed in the dielectric matrix of KBr, KCl and NaCl In this work copper oxide (CuO) and dysprosium oxide (Dy2O3) nanocrystals doped KBr, KCl and NaCl single crystals have been grown by Czochralski (Cz) method.
The effects of doping on the structural and optical properties of the host matrices have been studied.
The structural studies of samples were performed by XRD, μ-Raman, IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX).The treatment of XRD spectrum confirms the existence of crystallites of dopants (Sb2O3 and Y2O3) in the nanometer regime;Studies by μ-Raman and IR confirmed the
presence of chemical bonds Dy—Oand Cu—O in the different matrices.
The morphological study using the scanning electron microscope (SEM) shows that the micron grains scattered on the surface. The microscopic size of these aggregates is due to the fact that the nanocrystals have a tendency to reduce its free energy (Gibbs energy) of surface. The energy dispersive X-ray analysis (EDX) spectrum indicates that
the NaCl:CuO single crystal has a very high purity.
The optical absorption and photoluminescence shows that the optical gaps of the crystallites (CuO and Dy2O3) have been shifted to the high energy due to the quantum confinement effect of the charges.
The samples have important intense luminescence properties in the ultraviolet range. This feature makes these materials candidates which might come in the manufacture of components for optical systems using shorter wavelengths.
