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Elaboration et caractérisation de matériaux composites à base des nanoparticules du semi-conducteur CuO et de l’oxyde de terre rare Dy2O3 dispersées dans les matrices diélectriques KBr, KCl et NaCl. / Samiya Addala  

Public ISBD Titre : Elaboration et caractérisation de matériaux composites à base des nanoparticules du semi-conducteur CuO et de l’oxyde de terre rare Dy2O3 dispersées dans les matrices diélectriques KBr, KCl et NaCl. Type de document : texte imprimé Auteurs : Samiya Addala, Auteur ; O. Halimi, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 106 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais Physique Tags : NaCl  KCl  KBr  semiconducteur (CuO)  oxyde de terre rare (Dy2O3)  Czochralski  DRX  FT-IR  µ-Ramn  MEB-EDX  UV-Visible  photoluminescence  semiconductor (CuO)  rare earth oxide (Dy2O3)  XRD  IR  ?-Ramn  Uvi-Vis  ???????? ???????????  ??? ?????? )CuO(  ??????)Dy2O3)  ????? ?????????  ?????? ???? X  ???????? ??????  ???? ????? ? ?????? ?? ??? ???????  ?????? ?????????? ?????? MEB Index. décimale : 530 Physique 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. Diplôme : Doctorat en sciences En ligne : ../theses/physique/ADD6746.pdf Format de la ressource électronique : pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9870 Elaboration et caractérisation de matériaux composites à base des nanoparticules du semi-conducteur CuO et de l’oxyde de terre rare Dy2O3 dispersées dans les matrices diélectriques KBr, KCl et NaCl. [texte imprimé] / Samiya Addala, Auteur ; O. Halimi, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 106 f. ; 30 cm. 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais Physique Tags : NaCl  KCl  KBr  semiconducteur (CuO)  oxyde de terre rare (Dy2O3)  Czochralski  DRX  FT-IR  µ-Ramn  MEB-EDX  UV-Visible  photoluminescence  semiconductor (CuO)  rare earth oxide (Dy2O3)  XRD  IR  ?-Ramn  Uvi-Vis  ???????? ???????????  ??? ?????? )CuO(  ??????)Dy2O3)  ????? ?????????  ?????? ???? X  ???????? ??????  ???? ????? ? ?????? ?? ??? ???????  ?????? ?????????? ?????? MEB Index. décimale : 530 Physique 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. Diplôme : Doctorat en sciences En ligne : ../theses/physique/ADD6746.pdf Format de la ressource électronique : pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9870

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Code-barres	Cote	Support	Localisation	Section	Disponibilité
ADD/6746	ADD/6746	Thèse	Bibliothèque principale	Thèses	Disponible