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Titre : Cupric Oxide thin films deposition for gas sensor application Type de document : texte imprimé Auteurs : Meryem Lamri Zeggar, Auteur ; Mohamed Salah Aida, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 225 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Anglais (eng) Tags : couches minces CuO spray pyrolyse cellules solaire capteur à gaz thin films spray pyrolysis solar cells gas sensor ????? ?????, CuO???? ??????? ??????? ??????? ??? ??????? Index. décimale : 530 Physique Résumé :
The present work deals with the deposition of CuO thin films by a simple and cheap
technique such as Spray ultrasonic pyrolysis (SP). In the first, a set of CuO thin film was prepared using various deposition conditions in order to optimize the technique and prepare suitable films devoted to the photovoltaic and sensing applications. The studied deposition parameters were the substrate temperature, flow rate, salt nature and concentration. The structural analysis shows that the obtained films are polycrystalline, they exhibit a monoclinic structure. The preferential orientation is strongly related to the experimental parameters studies. From the optical and electrical characterization results, we inferred that the deposited films have suitable optoelectronic properties for the photovoltaic applications since they present a good absorption in the visible range. The fabricated CuO based sensor show a very high sensitivity equivalent to 90% at lower operation temperature equal to 50°C towards 300 ppm of methanol vapor. The sensing layer exhibits response and recovery times of 2,45 min and 2,02 min respectively with limit detection equal to 20 ppm. For ethanol sensing, the CuO based gas sensor show a sensitivity equal to 45% towards 300 ppm concentration of ethanol at operation temperature equal to 150°C. Response and recovery times are 2,98 min and 2,11 min respectively with limit detection at 25 ppm. The fabricated CuO based gas sensor show also a relative gas response equal to 9% at lower operation temperature above 60°C for CO2 pressure at 5hPa. The response and recovery times are ranged from 29 to 41 s and 30 to 35 s respectively occurring increases in sensitivity from 4.67 to 13.46 % when varying the CO2 pressure from 2 to 20 hPa. The obtained solar cells devices for CuO/ZnO and CuO/ZnS have low efficiencies equal to 5.2 x 10-4 and 7 x 10-4 %, respectively.Diplôme : Doctorat En ligne : ../theses/physique/LAM6909.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10244 Cupric Oxide thin films deposition for gas sensor application [texte imprimé] / Meryem Lamri Zeggar, Auteur ; Mohamed Salah Aida, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2016 . - 225 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Anglais (eng)
Tags : couches minces CuO spray pyrolyse cellules solaire capteur à gaz thin films spray pyrolysis solar cells gas sensor ????? ?????, CuO???? ??????? ??????? ??????? ??? ??????? Index. décimale : 530 Physique Résumé :
The present work deals with the deposition of CuO thin films by a simple and cheap
technique such as Spray ultrasonic pyrolysis (SP). In the first, a set of CuO thin film was prepared using various deposition conditions in order to optimize the technique and prepare suitable films devoted to the photovoltaic and sensing applications. The studied deposition parameters were the substrate temperature, flow rate, salt nature and concentration. The structural analysis shows that the obtained films are polycrystalline, they exhibit a monoclinic structure. The preferential orientation is strongly related to the experimental parameters studies. From the optical and electrical characterization results, we inferred that the deposited films have suitable optoelectronic properties for the photovoltaic applications since they present a good absorption in the visible range. The fabricated CuO based sensor show a very high sensitivity equivalent to 90% at lower operation temperature equal to 50°C towards 300 ppm of methanol vapor. The sensing layer exhibits response and recovery times of 2,45 min and 2,02 min respectively with limit detection equal to 20 ppm. For ethanol sensing, the CuO based gas sensor show a sensitivity equal to 45% towards 300 ppm concentration of ethanol at operation temperature equal to 150°C. Response and recovery times are 2,98 min and 2,11 min respectively with limit detection at 25 ppm. The fabricated CuO based gas sensor show also a relative gas response equal to 9% at lower operation temperature above 60°C for CO2 pressure at 5hPa. The response and recovery times are ranged from 29 to 41 s and 30 to 35 s respectively occurring increases in sensitivity from 4.67 to 13.46 % when varying the CO2 pressure from 2 to 20 hPa. The obtained solar cells devices for CuO/ZnO and CuO/ZnS have low efficiencies equal to 5.2 x 10-4 and 7 x 10-4 %, respectively.Diplôme : Doctorat En ligne : ../theses/physique/LAM6909.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10244 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique / Adel Taabouche
Titre : Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique Type de document : texte imprimé Auteurs : Adel Taabouche, Auteur ; A. Bouabellou, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 107 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Sciences des matériaux Couche mince ZnO PLD Spray DRX AFM RBS M-lines UV-visible Effet Hall Thin films XRD Hall Effect ????? ????? ????????? ??????? ???? ??? ?????? ?????? ??????
??????? ??????? ??????? ??????? ?????? ??????? ??? ???Index. décimale : 530 Physique Résumé : In the present work, we have studied essentially the structural and optical properties of ZnO thin films elaborated using the physical technique s of the pulsed laser ablation (PLD) and the chemical method of the ultrasonic spray pyrolysis.
We have prepared undoped (ZnO) and cobalt-doped zinc oxide (CZO) thin films (Co: 3,5 at.%) by means of the PLD method. Synthesized films have been deposited on glass and silicon substrates heated at 450°C. The used source was a KrF eximer laser (248 nm, 25 ns, 2 J ⁄cm2). Different experimental techniques have been carried out to analyze the fabricated films: the X-ray diffraction (XRD), atomic force microscopy (AFM), Rutherford Backscattering spectrometry (RBS), UV-visible spectrophotometry, M-lines
spectroscopy and Hall effect.
While the ZnO films obtained by the ultrasonic spray technique have been deposited with different deposition times (10, 20, 30 min) on a glass substrate heated at 410 °C, and then they have characterized by XRD, AFM, UV-visible, M-lines and hall effect techniques.
The carried out study shows that all the prepared zinc oxide films have a hexagonal wurtzite-type structure and a preferentially oriented along the direction (002) confused with the c-axis perpendicular to the surface of the substrates. The grain sizes deducted from the XRD measurements vary between 24 and 40 nm. The optical coupling analysis realized by M-lines show that the ZnO films are monomode (for both TE and TM polarizations). However, the undoped ZnO film obtained by PLD is found to be two
guiding modes for TM. The films obtained have an optical transmission of 70 to 90% in the visible region of the spectrum and an optical band gap varying from 3.18 to 3.37 eV.
The electrical conductivity and the concentration of carriers, deduced from Hall effect measurements, are relatively low namely for the films prepared by spray pyrolysis technique.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TAA6719.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9904 Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique [texte imprimé] / Adel Taabouche, Auteur ; A. Bouabellou, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 107 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Sciences des matériaux Couche mince ZnO PLD Spray DRX AFM RBS M-lines UV-visible Effet Hall Thin films XRD Hall Effect ????? ????? ????????? ??????? ???? ??? ?????? ?????? ??????
??????? ??????? ??????? ??????? ?????? ??????? ??? ???Index. décimale : 530 Physique Résumé : In the present work, we have studied essentially the structural and optical properties of ZnO thin films elaborated using the physical technique s of the pulsed laser ablation (PLD) and the chemical method of the ultrasonic spray pyrolysis.
We have prepared undoped (ZnO) and cobalt-doped zinc oxide (CZO) thin films (Co: 3,5 at.%) by means of the PLD method. Synthesized films have been deposited on glass and silicon substrates heated at 450°C. The used source was a KrF eximer laser (248 nm, 25 ns, 2 J ⁄cm2). Different experimental techniques have been carried out to analyze the fabricated films: the X-ray diffraction (XRD), atomic force microscopy (AFM), Rutherford Backscattering spectrometry (RBS), UV-visible spectrophotometry, M-lines
spectroscopy and Hall effect.
While the ZnO films obtained by the ultrasonic spray technique have been deposited with different deposition times (10, 20, 30 min) on a glass substrate heated at 410 °C, and then they have characterized by XRD, AFM, UV-visible, M-lines and hall effect techniques.
The carried out study shows that all the prepared zinc oxide films have a hexagonal wurtzite-type structure and a preferentially oriented along the direction (002) confused with the c-axis perpendicular to the surface of the substrates. The grain sizes deducted from the XRD measurements vary between 24 and 40 nm. The optical coupling analysis realized by M-lines show that the ZnO films are monomode (for both TE and TM polarizations). However, the undoped ZnO film obtained by PLD is found to be two
guiding modes for TM. The films obtained have an optical transmission of 70 to 90% in the visible region of the spectrum and an optical band gap varying from 3.18 to 3.37 eV.
The electrical conductivity and the concentration of carriers, deduced from Hall effect measurements, are relatively low namely for the films prepared by spray pyrolysis technique.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TAA6719.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9904 Exemplaires
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Titre : Élaboration et caracterisation des films ZnS par bain chimique Type de document : texte imprimé Auteurs : Hichem Lekiket, Auteur ; Mohamed Salah Aida, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 116 f. Format : 30 cm. Note générale : 2 copies imprimes disponibles Langues : Français (fre) Tags : Science des matériaux semi-conducteurs Couches minces Sulfure de zinc Bain chimique Cellules solaires Thin films Zinc sulfide Chemical bath Solar cells ??????? ??????? ??????? ????? Index. décimale : 530 Physique Résumé : The present work deals with the study of ZnS thin film synthesis by chemical bath deposition
technique (CBD). The latter is known to be cheap and simple which motivates our choice of
this method. We have used Zinc sulfate (ZnSO4), Thiourea (CS(NH2)2), ammonia (NH3) and
hydrazine (N2H4). thin films were prepared with two different parameters such as the pH
and the solution temperature. The structural, optical and electrical properties of the obtained
films were characterized by means of several techniques. From structural studies of ZnS films
we inferred that ZnS films have a cubic structure with a preferential orientation (111).
The optical studies reveal that ZnS films have a large transparency in the visible range. This
comforts their using as buffer layer in thin films solar cells.Diplôme : Doctorat en sciences En ligne : ../theses/physique/LEK6849.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10146 Élaboration et caracterisation des films ZnS par bain chimique [texte imprimé] / Hichem Lekiket, Auteur ; Mohamed Salah Aida, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2016 . - 116 f. ; 30 cm.
2 copies imprimes disponibles
Langues : Français (fre)
Tags : Science des matériaux semi-conducteurs Couches minces Sulfure de zinc Bain chimique Cellules solaires Thin films Zinc sulfide Chemical bath Solar cells ??????? ??????? ??????? ????? Index. décimale : 530 Physique Résumé : The present work deals with the study of ZnS thin film synthesis by chemical bath deposition
technique (CBD). The latter is known to be cheap and simple which motivates our choice of
this method. We have used Zinc sulfate (ZnSO4), Thiourea (CS(NH2)2), ammonia (NH3) and
hydrazine (N2H4). thin films were prepared with two different parameters such as the pH
and the solution temperature. The structural, optical and electrical properties of the obtained
films were characterized by means of several techniques. From structural studies of ZnS films
we inferred that ZnS films have a cubic structure with a preferential orientation (111).
The optical studies reveal that ZnS films have a large transparency in the visible range. This
comforts their using as buffer layer in thin films solar cells.Diplôme : Doctorat en sciences En ligne : ../theses/physique/LEK6849.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10146 Exemplaires
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Titre : Realization and electrical characterization of thin film heterojunction for photovoltaic application. Type de document : texte imprimé Auteurs : Fatima Zohra Boutebakh, Auteur ; Nadhir Attaf, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 173 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Anglais (eng) Tags : couches minces CZTS spray pyrolyse hétérojonction cellules solaire thin films spray pyrolysis hetero-junction solar cells ????? ????? CZTS???? ??????? ???? ??? ??????? ??????? ??????? Index. décimale : 530 Physique Résumé : The present work deals with the deposition of CZTS thin films and related devices by a simple and cheap technique such as Spray Pyrolysis (SP). For this purpose, a set of CZTS thin film was prepared using various deposition conditions in order to optimize the deposition conditions allow us to prepare suitable films devoted to the photovoltaic applications. The studied deposition parameters were the substrate temperature, deposition time, and copper and zinc salt concentrations. The structural analysis shows that the obtained films are polycrystalline; they exhibit a tetragonal structure with a preferential orientation along (112). However, the structural properties and secondary phases were affected by the deposition conditions. From the optical and electrical characterization results, we inferred that the deposited films have suitable optoelectronic properties for the photovoltaic applications, since they present a good absorption in the visible range coupled with a higher conductivity. Finally; the fabricated CZTS heterojunction with various back contacts show a rectification behavior, the G-f characterization reveals the presence of interface state at CZTS/ZnS interface with a state density in the order of 1010 eV-1cm-2. The addition of ZnO intrinsic layer enhances the heterojunction device properties. Whereas, the solar cells based CZTS/CdS annealed at 450 °C under H2S gas show the best solar cell efficiency about 0.43 % and a current density equal 9.8 mA/cm2.
Diplôme : Doctorat En ligne : ../theses/physique/BOU7355.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11004 Realization and electrical characterization of thin film heterojunction for photovoltaic application. [texte imprimé] / Fatima Zohra Boutebakh, Auteur ; Nadhir Attaf, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 173 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Anglais (eng)
Tags : couches minces CZTS spray pyrolyse hétérojonction cellules solaire thin films spray pyrolysis hetero-junction solar cells ????? ????? CZTS???? ??????? ???? ??? ??????? ??????? ??????? Index. décimale : 530 Physique Résumé : The present work deals with the deposition of CZTS thin films and related devices by a simple and cheap technique such as Spray Pyrolysis (SP). For this purpose, a set of CZTS thin film was prepared using various deposition conditions in order to optimize the deposition conditions allow us to prepare suitable films devoted to the photovoltaic applications. The studied deposition parameters were the substrate temperature, deposition time, and copper and zinc salt concentrations. The structural analysis shows that the obtained films are polycrystalline; they exhibit a tetragonal structure with a preferential orientation along (112). However, the structural properties and secondary phases were affected by the deposition conditions. From the optical and electrical characterization results, we inferred that the deposited films have suitable optoelectronic properties for the photovoltaic applications, since they present a good absorption in the visible range coupled with a higher conductivity. Finally; the fabricated CZTS heterojunction with various back contacts show a rectification behavior, the G-f characterization reveals the presence of interface state at CZTS/ZnS interface with a state density in the order of 1010 eV-1cm-2. The addition of ZnO intrinsic layer enhances the heterojunction device properties. Whereas, the solar cells based CZTS/CdS annealed at 450 °C under H2S gas show the best solar cell efficiency about 0.43 % and a current density equal 9.8 mA/cm2.
Diplôme : Doctorat En ligne : ../theses/physique/BOU7355.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11004 Exemplaires
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Titre : Elaboration et caractérisation de nanocomposites hybrides : Oxydes métalliques/polymères Type de document : texte imprimé Auteurs : Bariza Troudi, Auteur ; Ouahiba Halimi, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 121 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Synthèse hydrothermale Nanocomposites Films minces CuO/PS CuO/PVC PbO/PS PbO/PVC DRX FT-IR Raman AFM Absorption UV-Visible photoluminescence Hydrothermal synthesis thin films UV-Visible Absorption ?????? ?????? ????? ????? ???????? ??? ????????- ???? ???????? ?????? Index. décimale : 530 Physique Résumé : Thin films of metal oxides/polymers nanocomposites were deposited on glass substrates by Spin-Coating and Dip-Coating techniques. The nanocomposites were elaborated by inserting, in the matrices of polystyrene (PS) and polyvinyl chloride (PVC) polymers, of nanoparticles of metal oxides such as copper oxide (CuO) and lead oxide (PbO). The nanoparticles of semiconductor CuO and PbO were synthesized beforehand by the hydrothermal method. The xray diffraction characterization of the obtained powders have revealed a monoclinic phase for CuO crystallites and an orthorhombic phase for PbO. The size of the crystallites of the two semiconductors is of a nanometic order. Calcul the of gap energy indicate a shift towards high energies compared to massive crystals. This shift is due to the effect of the quantum confinement induced by the nanometric size of the crystallites of the semiconductors. These nanocrystals are used for the preparation of the nanocomposites of CuO/PS, CuO/PVC, PbO/PS and PbO/PVC by
simple insertion of CuO and PbO nanoparticles in the PS and PVC polymers. The analysis of the elaborated nanocomposites by X-ray diffraction has allowed to notice the incorporation of the CuO and PbO crystallites into the PS and PVC polymers matrixes and analysis by Raman and infrared spectroscopies has confirmed the presence of CuO and PbO crystallites in the PS and PVC matrixes by revealing specific vibration modes to the Cu-O and Pb-O bonds. The surface morphology and topography of thin films of nanocomposites were highlighted with the help of atomic force microscopy (AFM) and have shown homogeneous dispersion of CuO and PbO crystallites and a low surface roughness. the characterization by measurement of the optical absorption in the UV-Visible domain allows to observe the increase in optical absorption which is attributed to CuO and PbO nanocrystallites because PS and PVC are optically transparent in the UV-Visible domain. A shift of the gap energy of the nanocomposites compared with the gap energy of the pure polymers and the massive crystallites of CuO and PbO was observed. This variation in gap energy is the result of the new optical behavior of the prepared nanocomposites.
The optical characterization by the measure of the photoluminescence has shown that the elaborated samples present intense luminescence bands in the visible range, hence the possibility of consider these matrices as optically active media and can be used for the making devices of specific optics properties.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TRO7142.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10460 Elaboration et caractérisation de nanocomposites hybrides : Oxydes métalliques/polymères [texte imprimé] / Bariza Troudi, Auteur ; Ouahiba Halimi, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2017 . - 121 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Synthèse hydrothermale Nanocomposites Films minces CuO/PS CuO/PVC PbO/PS PbO/PVC DRX FT-IR Raman AFM Absorption UV-Visible photoluminescence Hydrothermal synthesis thin films UV-Visible Absorption ?????? ?????? ????? ????? ???????? ??? ????????- ???? ???????? ?????? Index. décimale : 530 Physique Résumé : Thin films of metal oxides/polymers nanocomposites were deposited on glass substrates by Spin-Coating and Dip-Coating techniques. The nanocomposites were elaborated by inserting, in the matrices of polystyrene (PS) and polyvinyl chloride (PVC) polymers, of nanoparticles of metal oxides such as copper oxide (CuO) and lead oxide (PbO). The nanoparticles of semiconductor CuO and PbO were synthesized beforehand by the hydrothermal method. The xray diffraction characterization of the obtained powders have revealed a monoclinic phase for CuO crystallites and an orthorhombic phase for PbO. The size of the crystallites of the two semiconductors is of a nanometic order. Calcul the of gap energy indicate a shift towards high energies compared to massive crystals. This shift is due to the effect of the quantum confinement induced by the nanometric size of the crystallites of the semiconductors. These nanocrystals are used for the preparation of the nanocomposites of CuO/PS, CuO/PVC, PbO/PS and PbO/PVC by
simple insertion of CuO and PbO nanoparticles in the PS and PVC polymers. The analysis of the elaborated nanocomposites by X-ray diffraction has allowed to notice the incorporation of the CuO and PbO crystallites into the PS and PVC polymers matrixes and analysis by Raman and infrared spectroscopies has confirmed the presence of CuO and PbO crystallites in the PS and PVC matrixes by revealing specific vibration modes to the Cu-O and Pb-O bonds. The surface morphology and topography of thin films of nanocomposites were highlighted with the help of atomic force microscopy (AFM) and have shown homogeneous dispersion of CuO and PbO crystallites and a low surface roughness. the characterization by measurement of the optical absorption in the UV-Visible domain allows to observe the increase in optical absorption which is attributed to CuO and PbO nanocrystallites because PS and PVC are optically transparent in the UV-Visible domain. A shift of the gap energy of the nanocomposites compared with the gap energy of the pure polymers and the massive crystallites of CuO and PbO was observed. This variation in gap energy is the result of the new optical behavior of the prepared nanocomposites.
The optical characterization by the measure of the photoluminescence has shown that the elaborated samples present intense luminescence bands in the visible range, hence the possibility of consider these matrices as optically active media and can be used for the making devices of specific optics properties.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TRO7142.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10460 Exemplaires
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