ABDELHAFID Mahroug

mahroug ouarda

Effet du solvant sur les propriétés physiques des films minces d’oxyde de zinc : élaboration et caractérisation

Meddah Ahlam

Influence du dopage par un élément de transition sur les propriétés physiques des films minces d’oxyde de zinc : Elaboration et Caractérisation

Benrezgua Elhadj

Synthesis, characterization and study of the properties of zinc oxide-based nanocomposites

Amari, Rabie

Etude de l'effet de dopage sur les propriétés physiques et chimiques des semiconducteurs à base d’oxyde synthétisées par la technique sol- gel spin coating.

Mecheter Imane

Physical Properties of Sol Gel Copper Oxide (CuO) Thin Films; Sol concentration effect

Khemaies Chahra

Synthèse et caractérisation de couches minces nanostructureés de ZnO/CuO par la technique sol-gel

The photocatalytic process is used to remove organic contaminants. The present study investigates the photocatalytic degradation of methylene blue by sol-gel-synthesized CuO/ZnO nanocomposites thin films with different CuO content. CuO/ZnO nanostructures thin films were characterized by X-ray diffraction (XRD), PL and UV–vis spectroscopies and photodegradation test. XRD results confirmed the presence of CuO and ZnO phases in the nanostructure thin films. By incorporation of the CuO compound, the gap energy of ZnO decreased, PL intensity reduced, and the absorption of films in the visible was enhanced. ZnO/CuO nanocomposites thin films exhibit an excellent performance of photocatalytic activity.

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Abdelhafid MAHROUG , ,(2023-12-02), Copper oxide/zinc oxide nanocomposites thin films: elaboration and their photodegradation properties,THE 1 ST NATIONAL CONFERENCE ON PHYSICS AND IT’S APPLICATIONS,BOUSAADA

CuO/ZnO nanostructures thin films were characterized by X-ray diffraction (XRD), PL and UV–vis spectroscopies and photodegradation test. XRD results confirmed the presence of CuO and ZnO phases in the nanostructure thin films. By incorporation of the CuO compound, the gap energy of ZnO decreased, PL intensity reduced, and the absorption of films in the visible was enhanced. ZnO/CuO nanocomposites thin films exhibit an excellent performance of photocatalytic activity

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Abdelhafid MAHROUG , ,(2023-09-23), Characterization and photocatalytic activity of Sol Gel copper oxide/zinc oxide nanocomposites thin films,3rd International Conference on Innovative Academic Studies,Konya/Turkey

Zinc oxide is an important oxide semiconductor, with excellent physical and chemical properties that are used in different applications fields. In this research paper, ZnO thin films were synthesized using different types of solvent by sol-gel spin coating technique. The effect of solvent on the structural, morphological, photocurrent and optical properties of the films has been studied. X-ray diffraction revealed the high crystallinity of films in the wurtzite structure with a c-axis preferred orientation. SEM micrographs revealed that all films exhibit a fibrous structure, where the more homogeneous and dense surfaces were observed for ZnO-2-PrOH and ZnO–EtOH films. The optical properties analysis shows that the films have high transparency. Different structural and optical parameters were influenced by the type of solvent, where ZnO-2-PrOH film displays an improvement in structural and optical properties. The photoluminescence PL spectrum revealed three emissions, two green emissions and a UV emission at 390 nm. ZnO-2-PrOH film exhibits a high intensity ratio of UV to visible (IUV/Ivis), a best UV response, and photocurrent properties. Finally, structural and optical parameters were also calculated by first-principles DFT calculations, discussed, and compared to those experimental.

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Abdelhafid MAHROUG , , (2023-06-16), Optical, luminescence, photocurrent and structural properties of sol-gel ZnO fibrous structure thin films for optoelectronic applications: A combined experimental and DFT study, optical materials, Vol:142, Issue:6, pages:114043, elsevier

Zinc oxide is an important oxide semiconductor, with excellent physical and chemical properties that are used in different applications fields. In this research paper, ZnO thin films were synthesized using different types of solvent by sol-gel spin coating technique. The effect of solvent on the structural, morphological, photocurrent and optical properties of the films has been studied. X-ray diffraction revealed the high crystallinity of films in the wurtzite structure with a c-axis preferred orientation. SEM micrographs revealed that all films exhibit a fibrous structure, where the more homogeneous and dense surfaces were observed for ZnO-2-PrOH and ZnO– EtOH films. The optical properties analysis shows that the films have high transparency. Different structural and optical parameters were influenced by the type of solvent, where ZnO-2-PrOH film displays an improvement in structural and optical properties. The photoluminescence PL spectrum revealed three emissions, two green emissions and a UV emission at 390 nm. ZnO-2-PrOH film exhibits a high intensity ratio of UV to visible (IUV/ Ivis), a best UV response, and photocurrent properties. Finally, structural and optical parameters were also calculated by first-principles DFT calculations, discussed, and compared to those experimental.

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Djamel ALLALI , Abdelhafid MAHROUG , SAMIR Hamrit , , (2023-06-16), Optical, luminescence, photocurrent and structural properties of sol-gel ZnO fibrous structure thin films for optoelectronic applications: A combined experimental and DFT study, Optical Materials, Vol:142, Issue:, pages:114043, Elsevier

polycopié Mécanique des fluides

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AbdelhafidMAHROUG , ,(2023-06-12); polycopié Mécanique des fluides,m'sila university,

polycopié Mécanique du point materiel

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AbdelhafidMAHROUG , ,(2023-04-10); polycopié Mécanique du point materiel,m'sila university,

Due to its excellent physical and chemical properties, transition metal-doped zinc oxide has potential applications in different fields. In this research paper, pure and iron-doped ZnO films were deposited by thermal oxidation of sputtered metallic zinc and iron. The effect of iron (Fe) doping on the optical, morphology, structural, electrical, and photocurrent properties of zinc oxide films was examined. The X-ray diffraction analysis shows a wurtzite structure with preferential orientation for all films, where the high texture coefficient values (above 3) corresponded to the (002) plane. Fe doping reduced the crystallite size from 12.3 to 8.7 nm and lattice constants c and a values from 5.19 to 5.155 Å and from 3.236 to 3.203 Å respectively. The different calculated structure parameters, confirm the incorporation of Fe (Fe3+) in the ZnO lattice. The surface morphology of thin films measured using atomic force microscopy revealed that the Fe doping could markedly decrease the grains size from 248 to 54 nm and the Root–Mean–Square roughness of films from 5.27 to 4.22 nm. For all films, the transmittance analysis shows a transmittance above 90% in the visible region and with an increase in the Fe concentration, the transmittance, and the absorption in the ultraviolet region were increased. The gap energy of ZnO strongly increased from 3.26 to 3.51 eV with doping. The effect of Fe doping on different optical parameters was discussed in detail. The photoluminescence analysis of pure and doped ZnO exhibits one ultraviolet emission (384 nm) and green emission. Compared to pure ZnO, the ultraviolet peak intensity decreased as Fe content increased. The electrical resistivity was decreased and the photocurrent properties of ZnO were enhanced by Fe doping. In this report, Fe-doped ZnO films exhibited remarkable properties. Therefore such films can be usefully used in different device applications.

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Abdelhafid MAHROUG , , (2023-03-24), Optical, Photocurrent, Electrical, Structural, and Morphological Properties of Magnetron Sputtered Pure and Iron-Doped Zinc Oxide Thin Films, ECS Journal of Solid State Science and Technology, Vol:12, Issue:3, pages:046006, iopscience

As an important metal oxide semiconductor, transition metal-doped zinc oxide (ZnO) has attracted great interest for various applications in optoelectronic, spintronic photovoltaic and photodetectors due to its significant chemical and physical properties. In this research study, pure and nickel (Ni)-doped ZnO nanostructured films were synthesized via the sol-gel method using the spin coating technique on glass substrates. The structural results revealed that all samples exhibited a polycrystalline wurtzite structure and a (002) plane preferred orientation. The crystallite size was reduced by Ni doping. The morphology micrographs indicate that the surface of thin films shows nanofiber structures. An optical study revealed the high transparency of the films. The photoluminescence (PL) showed one ultraviolet (UV) emission at 387 nm and different defect emissions for all films. The absorption, band gap and PL emissions intensities were influenced by Ni doping. Ni-doped ZnO nanostructured thin films revealed high UV sensitivity and photoresponse. Therefore, these thin films are a promising material for a UV photodetector. The dielectric function, absorption coefficient and energy band gap were also calculated and discussed by density functional theory (DFT), using the Ultra Soft Pseudo Potential (USPP) approach implemented in the CASTEP code.

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Abdelhafid MAHROUG , , (2022), Experimental and DFT study of structural and optical properties of Ni-doped ZnO nanofiber thin films for optoelectronic applications, optical materials, Vol:134, Issue:12, pages:113188, elsevier

In this work, ZnO thin films have been deposited on glass substrates by sol–gel spin coating method. Zinc acetate dihydrate, isopropanol and monoethanolamine (MEA) were used as a precursor, solvent and stabilizer, respectively. In order to study the effect of molarity on structural and optical properties, different solutions of 0.5, 1, 1.2, 1.5M have been prepared. The X-ray diffraction shows the high crystallinity of all films with the preferred orientation. The optical measurements by UV-Vis confirmed that our films exhibit transparent semiconductor properties to visible light. Increase the molarity leads to the decrease in transmittance and the value of the bandgap.

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Abdelhafid MAHROUG , ,(2022), Elaboration and characterization of Zinc Oxide thin films by sol-gel spin coating technique,1st International Conference on Innovative Academic Studies,Konya, Turkey

High quality of Al doped ZnO thin films were prepared using a sol–gel spin coating method. The result of XRD indicates that the film is polycrystalline hexagonal wurtzite structure with good crystallinity. Small grains in the film were observed in AFM image with average grains size of 52nm and surface roughness of 7nm. The film has an average transmittance above 95% in the visible region and optical band gap energy of 3.29eV. The photocurrent measurement result indicates the better photocurrent properties of film.

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Abdelhafid MAHROUG , ,(2022), Sol gel of Al doped ZnO thin films: preparation and characterization,3rd International Conference on Applied Engineering and Natural Sciences,Konya, Turkey

In this study, the thickness effect of 4% Mn-doped ZnO thin films on structural, optical, and morphological properties is investigated. The films are deposited on a glass substrate using the sol-gel spin coating method. Phase analysis indicates that all films have a hexagonal wurtzite structure with a high preferential c-axis orientation. All structural parameters are significantly influenced by the thickness variations. The optical analysis reveals that transmittance and band gap energy decrease with thickness. A red shift of the absorption edge is noticed. The surface morphology shows a good uniformity for all ZnO films. The surface roughness of the samples increases with film thicknesses. The photoluminescence (PL) spectra show a UV peak at 388 nm with two blue peaks at 438 and 475 nm and a weak green emission peak at 525 nm. A lower PL intensity is noticed by increasing the thickness. The obtained results exhibit similarities in behavior as other methods.

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AMMAR Boukhari , Bahri DEGHFEL , Abdelhafid MAHROUG , Rabie AMARI , Noureddine Selmi, Ahmad Azmin Mohamad, , (2021), Thickness Effect on the Properties of 4% Mn‐Doped ZnO Thin Films Grown by Sol‐Gel Spin Coating Deposition, Macromolecular Symposia, Vol:397, Issue:1, pages:2000235, Wiley Online Library

The current study investigates the effect of thickness on the structural, morphological, electronic, and optical properties of pure zinc oxide (ZnO) and 7% Mn-doped ZnO thin films, deposited by sol–gel spin coating method. All films exhibited a hexagonal wurtzite structure with a high preferential c-axis orientation. The surface morphology showed a good uniformity with cracks and wrinkles. The transmittance decreased with thickness. The bandgap energy was inversely varying with coating number. Photoluminescence spectra showed ultraviolet with strong and weak blue and weak green emission peaks. Density functional theory and Hubbard (DFT + U) method was then applied to study the structural, electronic, and optical properties of pure and 6.25% Mn-doped ZnO materials. A decrease in bandgap energy from pure to 6.25% Mn-doped ZnO material was shown using the DFT + U method. It also found that the Mn3d states were distributed far from Fermi level with a coexistence of both ionic and covalent nature bonds. A slight shift toward the lower energy was noticed for optical properties by Mn doping. The theoretical findings showed a similar behavior to those obtained by experiment.

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AMMAR Boukhari , Bahri DEGHFEL , Abdelhafid MAHROUG , Rabie AMARI , Noureddine Selmi, Soorathep Kheawhom, Ahmad Azmin Mohamad, , (2021), Thickness effect on the properties of Mn-doped ZnO thin films synthesis by sol-gel and comparison to first-principles calculations, Ceramics International, Vol:47, Issue:12, pages:17276-17285, Elsevier

Pure and copper-doped zinc oxide thin films at different contents x (Zn1-xCuxO; 0≤x ≤ 0.125) were synthesized by sol–gel spin coating process and investigated using various techniques. All samples exhibited a polycrystalline with wurtzite hexagonal phase, which wasn't altered and getting relaxed by Cu-doping. The grain size increased and changed its growth mode from c-axis growth to lateral one and the surface morphology was strongly influenced with increasing level of Cu doping. As x increased, the transparency of films was generally increased in the visible region and the band gap energy (Eg) presented a slight shrinking, indicating that the prepared films are suitable for use in opto-electronic applications. Ferromagnetic phase was adopted within density functional theory corrected by Hubbard method (DFT + LDA + U) to investigate the structural, electronic, magnetic and optical properties of pure and CZO structure. The closest Cu impurities gave the more stable configuration. Cu3d states were distributed around Fermi level inducing a major contribution to the magnetic moment. A mix of ionic and covalent bonding was remarked. DFT + LDA + U enhanced significantly the calculated Eg, which presented a narrowing with x. The imaginary part of the dielectric functions presented three main peaks and their static constants were slightly influenced by Cu doping.

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Bahri DEGHFEL , Abdelhafid MAHROUG , AMMAR Boukhari , Rabie AMARI , elhadj.benrezgua@univ-msila.dz, Muhamad Kamil Yaakob, Soorathep Kheawhom, Ahmad Azmin Mohamad, , (2021), Experimental and theoretical studies on structural, morphological, electronic, optical and magnetic properties of Zn1-xCuxO thin films (0≤ x≤ 0.125), Materials Science in Semiconductor Processing, Vol:134, Issue:, pages:106012, Elsevier

In this study,7% Mn-doped ZnO thin film was deposited on glass substrate using sol–gel spin coating method at 0,7 ZnO concentration, in order to investigate the structural, optical and morphological properties. XRD result exhibit that the deposited thin film has a hexagonal wurtzite structure with a preferential orientation along the (0 0 2) c-axis orientation. The grain size, lattice constants, FWHM and strain of the film were calculated. To characterize the electronic and optical properties, UV-Vis spectra were used. The results indicate that the average transmittance is 45.15% in the visible range. The optical band gap energy was found to be 2.577 eV. The surface morphology showed a good uniformity with few cracks and wrinkles.

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AMMAR Boukhari , Bahri DEGHFEL , Abdelhafid MAHROUG , Ahmad Azmin Mohammad, ,(2021), Structural, morphological and optical properties of Mn-doped ZnO thin films prepared by sol-gel spin coating method,1st international conference on materials and energies (IC- ME-21),Tamanghasset - Algeria

In this study, a ZnO/CuO nanostructured thin film with number of layers is 8 layers (ZnO-CuO-ZnO-CuO ....) were synthesized on glass substrates by the sol–gel spin coating technique. Zinc acetate dihydrate, Copper chloride dihydrate, ethanol and monoethanolamine (MEA) were used as precursor, solvent and stabilizer, respectively. Structural, optical and luminescence properties of the ZnO/CuO nanostructured thin films were investigated by XRD, UV-Vis spectrometry and PL spectroscopy techniques. X-ray diffraction shows, the high crystallinity of nanocomposite films with preferential orientation and crystallite size is 20 nm. Photoluminescence of films showed emissions in the ultraviolet (UV) and several visible emissions such as violet, blue, green, yellow and red correspond to near-edge band (NBE) of ZnO and CuO and the different defects in both oxides. A sharp absorption edge has been observed for nanocomposite films in the region between 350 and 400 nm. This attributed to the absorption of light by nanocomposites oxides thin films. Elaborated of high quality of ZnO/CuO nanostructures thin films can be used in several applications such as: solar cells and photocatalysis.

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Abdelhafid MAHROUG , ,(2021), Synthesis and Characterization of ZnO/CuONanostructuresthin films by sol gel technique,1st International Conference on Sustainable Energy and Advanced Materials IC-SEAM’21 April 21-22, 2021, Ouargla, ALGERIA,Ouargla, ALGERIA

The structural, electronic and optical properties of Mn-doped ZnO thin films were studied using density functional theory (DFT) with Hubbard U method. Supercell model and substitutional method were employed to achieve the considered doping concentrations (x). Antiferromagnetic phase of Zn1−xMnxO (x = 0.125) structure was adopted at different geometry configurations. On the other hand, Zn1−xMnxO (x = 7, 10 and 12.5) thin films, with good uniformity, were fabricated using sol–gel spin coating technique. Both grain size and surface roughness were decreased with x, leading to the decrease of the average transmittance. Calculations revealed that Mn atoms tend to be close to each other around the O atom. Besides, Mn3d states were found to be rarely distributed around Fermi level. Furthermore, Mulliken analysis demonstrated the coexistence of both ionic and covalent bonding. Both materials presented a similar behavior for optical properties with a slight shift toward the lower energy by increasing x.

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Abdelhafid MAHROUG , , (2020), Effects of Mn doping on the structural, morphological, electronic and optical properties of ZnO thin films by sol-gel spin coating method: An experimental and DFT+U study, Physica B: Condensed Matter, Vol:577, Issue:15, pages:411766, sciencedirect

The structural, electronic and optical properties of Mn-doped ZnO thin films were studied using density functional theory (DFT) with Hubbard U method. Supercell model and substitutional method were employed to achieve the considered doping concentrations (x). Antiferromagnetic phase of Zn1−xMnxO (x = 0.125) structure was adopted at different geometry configurations. On the other hand, Zn1−xMnxO (x = 7, 10 and 12.5) thin films, with good uniformity, were fabricated using sol–gel spin coating technique. Both grain size and surface roughness were decreased with x, leading to the decrease of the average transmittance. Calculations revealed that Mn atoms tend to be close to each other around the O atom. Besides, Mn3d states were found to be rarely distributed around Fermi level. Furthermore, Mulliken analysis demonstrated the coexistence of both ionic and covalent bonding. Both materials presented a similar behavior for optical properties with a slight shift toward the lower energy by increasing x.

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Rabie AMARI , Bahri DEGHFEL , Abdelhafid MAHROUG , AMMAR Boukhari , Ahmad Azmin Mohamad, Noureddine Selmi, , (2020), Effects of Mn doping on the structural, morphological, electronic and optical properties of ZnO thin films by sol-gel spin coating method: An experimental and DFT+ U study, Physica B: Condensed Matter, Vol:577, Issue:15, pages:411766, North-Holland

In this study, a ZnO/CuO nanostructured thin films with number of layers is 8 layers (ZnO-CuO-ZnO-CuO ....) were synthesized on glass substrates by the sol–gel spin coating technique. Zinc acetate dihydrate, Copper chloride dihydrate, ethanol and monoethanolamine (MEA) were used as precursor, solvent and stabilizer, respectively. Structural, optical and luminescence properties of the ZnO/CuO nanostructured thin films were investigated by XRD, UV-Vis spectrometry and PL spectroscopy techniques. X-ray diffraction shows, the high crystallinity of nanocomposite films with preferential orientation and crystallite size is 20 nm. Photoluminescence of films showed emissions in the ultraviolet (UV) and several visible emissions such as violet, blue, green, yellow and red correspond to near-edge band (NBE) of ZnO and CuO and the different defects in both oxides. A sharp absorption edge has been observed for nanocomposite films in the region between 350 and 400 nm. This attributed to the absorption of light by nanocomposites oxides thin films. Elaborated of high quality of ZnO/CuO nanostructures thin films can be used in several applications such as: solar cells and photocatalysis.

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Abdelhafid MAHROUG , ,(2020), Synthesis and Characterization of CuO/ZnO Nanostructures thin films,1ère Conférence National sur la Transition Energétique en Algérie,M’sila, Algerié

ZnO and ZnCoO thin films have been deposited onto glass substrates by sol–gel spin coating method. Zinc acetate dihydrate, cobalt acetate tetrahydrate, Isopropanol and monoethanolamine (MEA) were used as a precursor, doping source, solvent and stabilizer respectively. The molar ratio of MEA to ions metal was maintained at 1.0 and a concentration of metal ions is 0.6 mol.L-1 . The XRD results showed that both films crystallized under hexagonal wurtzite structure and presented a preferential orientation along the c-axis with the maximum crystallite size was found is 25nm. Atomic force microscope (AFM) images revealed the good uniformity for both films, an increase of surface roughness is observed with doping. The average transmittance in the visible region was higher than 85% for both films and the optical band gap of Zinc oxide films decreased with Co doping. Photoluminescence of the films showed a ultraviolet (UV) and defect related visible emissions like violet, blue and green, and indicated that cobalt doping resulted in red shifting of UV emission and the reduction in the UV and visible emissions intensity. Ours thin films shows the best photocurrent properties.

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Abdelhafid MAHROUG , Bahri DEGHFEL , ,(2019), Studies on structural, surface morphological, optical, luminescence and uv photodetection properties of sol gel oxides thin films,ICAMS 2018 – 7th International Conference on Advanced Materials and Systems,Romania

Undoped and magnesium-doped zinc oxide thin films were prepared by the sol–gel method. Results from X-ray diffraction indicated that the films exhibited a hexagonal wurtzite structure and were highly oriented along the c-axis. The intensity of the (002) diffraction peak increased with increasing the Mg doping concentration. Also, Mg doping inhibited the growth of crystallite size which decreased from 46nm to 38nm with doping concentration. Morphological studies by atomic force microscopy (AFM) indicated the uniform thin film growth and the decreasing of grain size and surface roughness with Mg doping. Optical analysis showed that the average transmittance of all films was above 90% in the visible range and Mg doping has significantly enhanced the bandgap energy of ZnO. Two Raman modes assigned to E2L and E2H for the ZnO wurtzite structure were observed for all films. UV emission peak and three defect emission peaks in the visible region were observed by photoluminescence measurements at room temperature. The intensity ratio of UV emission to the visible emission increased with the Mg concentration. Photocurrent measurements revealed that all films presented the photoresponses with n-type semiconducting behavior and their generated photocurrents were reduced by Mg doping. The prepared thin films of high quality with improved properties by Mg doping could be proposed to workers in the field of optoelectronic devices for using them as a strong candidate.

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Abdelhafid MAHROUG , , (2019), STUDIES ON STRUCTURAL, SURFACE MORPHOLOGICAL, OPTICAL, LUMINESCENCE AND UV PHOTODETECTION PROPERTIES OF SOL–GEL Mg-DOPED ZnO THIN FILMS, Surface Review and Letters, Vol:26, Issue:3, pages:1850167, worldscientific

In this work, we have studied the influence of Mn doping on the structural, morphological, optical and photoluminescence (PL) properties of ZnO thin films. ZnO thin films with different concentrations of Manganese (0, 2 and 4 mol.%) were prepared by the sol–gel spin coating process and synthesized on glass substrates. By using an X-ray diffractometer (XRD) (Bruker 8 Advance) with Cu-kα radiation having a wavelength λ=1.5406 A°, the structural properties of the films were characterised. To evaluate the band gap, the optical transmission spectra were measured by an ultraviolet-visible (UV-vis) spectrophotometer (UV-3101 PC-Shimadzu) in the spectral range 300-800 nm. Photoluminescence (PL) measurements were recorded using a spectrofluorimeter (Perkin Elmer LS 50B) with the excitation wavelength of 325 nm.

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Rabie AMARI , Abdelhafid MAHROUG , Bahri DEGHFEL , ,(2018), Effect of Mn Doping on the Structural and Optical Properties of ZnO thin Films,International Conference on Materials Science (ICMS2018),Ferhat Abbas Setif 1-Algeria

Magnesuim doped Zinc oxide thin films were prepared by sol-gel spin coating method

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Abdelhafid MAHROUG , Amari Rabie , Boukhari Ammar , Bahri DEGHFEL , elhadj.benrezgua@univ-msila.dz, ,(2018), Deposition and Characterization of Mg doped nanostructured thin films,International Conference on Materials Science 2018 (ICMS2018),Sétif, Algeria

In this study, Manganese-doped Zinc oxide (ZnO) nanostructured thin films with different Mn doping concentrations (0, 1, 3, 5 and 7 mol.%) were synthesized on glass substrates by the sol–gel spin coating technique. The concentration of metal ions was fixed at 0.6 mol·L–1. Structural, surface morphological, optical and luminescence properties of the films were investigated by XRD, AFM, UV-Vis spectrometry and PL spectroscopy techniques. The XRD results showed that the films had hexagonal wurtzite structure and exhibited preferred orientation along the c-axis. Crystallite size, lattice parameters, strain and residual stress were influenced by Mn doping, where average crystallite size decreased from 45 to 10 nm with doping concentration. Atomic force microscope (AFM) images revealed the good uniformity for all the films, and reduction of grain size and surface roughness is observed with the increase of doping concentration. The average transmittance in the visible region was higher than 80% for all the films. Unlike the Urbach energy, the optical band gap of Zinc oxide films decreased with Manganese doping. The origin of ultraviolet, violet, blue and green emissions observed from photoluminescence spectra, and the effect of Mn doping on the luminescence properties and defects concentration were discussed in details. It is worth noting that the fabricated Zinc oxide (ZnO) thin films, which presented good properties, can be used for potential applications in optoelectronic devices.

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Abdelhafid MAHROUG , Amari Rabie , Boukhari Ammar , Bahri DEGHFEL , , (2018), Synthesis, Structural, Morphological, Electronic, Optical and Luminescence Properties of Pure and Manganese-Doped Zinc Oxide Nanostructured Thin Films: Effect of Doping, Journal of Nanoelectronics and Optoelectronics, Vol:13, Issue:5, pages:732, American Scientific Publishers

In this study, Manganese-doped Zinc oxide (ZnO) nanostructured thin films with different Mn doping concentrations (0, 1, 3, 5 and 7 mol.%) were synthesized on glass substrates by the sol–gel spin coating technique. The concentration of metal ions was fixed at 0.6 mol·L–1. Structural, surface morphological, optical and luminescence properties of the films were investigated by XRD, AFM, UV-Vis spectrometry and PL spectroscopy techniques. The XRD results showed that the films had hexagonal wurtzite structure and exhibited preferred orientation along the c-axis. Crystallite size, lattice parameters, strain and residual stress were influenced by Mn doping, where average crystallite size decreased from 45 to 10 nm with doping concentration. Atomic force microscope (AFM) images revealed the good uniformity for all the films, and reduction of grain size and surface roughness is observed with the increase of doping concentration. The average transmittance in the visible region was higher than 80% for all the films. Unlike the Urbach energy, the optical band gap of Zinc oxide films decreased with Manganese doping. The origin of ultraviolet, violet, blue and green emissions observed from photoluminescence spectra, and the effect of Mn doping on the luminescence properties and defects concentration were discussed in details. It is worth noting that the fabricated Zinc oxide (ZnO) thin films, which presented good properties, can be used for potential applications in optoelectronic devices.

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Abdelhafid MAHROUG , Rabie AMARI , AMMAR Boukhari , Bahri DEGHFEL , L Guerbous, Nourddine Selmi, , (2018), Synthesis, Structural, Morphological, Electronic, Optical and Luminescence Properties of Pure and Manganese-Doped Zinc Oxide Nanostructured Thin Films: Effect of Doping, Journal of Nanoelectronics and Optoelectronics, Vol:13, Issue:5, pages:732-742, American Scientific Publishers

Transparent zinc oxide (ZnO) thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations (0.3–1.2 M) using zinc acetate dehydrate [Zn(CH3COO)2·2H2O] as precursor and isopropanol and monoethanolamine (MEA) as solvent and stabilizer, respectively. The molar ratio of zinc acetate dehydrate to MEA is 1.0. X-ray diffraction, ultraviolet-visible spectroscopy and photoluminescence spectroscopy are employed to investigate the effect of solution concentration on the structural and optical properties of the ZnO thin films. The obtained results of all thin films are discussed in detail and are compared with other experimental data.

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AMMAR Boukhari , Abdelhafid MAHROUG , AMMAR Boukhari , Bahri DEGHFEL , NOURREDINE SELMI, , (2018), Structural, optical and luminescence properties of ZnO thin films prepared by sol-gel spin-coating method: effect of precursor concentration, Chinese Physics Letters, Vol:35, Issue:, pages:016801, IOP Publishing

Zn0.875Mn0.125O thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates using zinc acetate dehydrate [Zn(CH3COO)2·2H2O] and manganese acetate tetrahydrate [Mn(CH3COO)24H2O]as a starting material and doping source. Isopropanol and monoethanolamine (MEA) were used as solvent and stabilizer, respectively. X-ray diffraction, ultraviolet-visible spectroscopy and photoluminescence spectroscopy are employed to investigate the effect of Mn doping on the structural, electronic and optical properties of ZnO thin films. The obtained results are compared with those using first-principles calculation based on density functional theory (DFT) with local density approximation (LDA) plus Hubbard U (DFT–LDA+U) method. This latter represents the theoretical framework to deal with strongly correlated materials to predicted successfully the electronic properties of such materials.

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Bahri DEGHFEL , Abdelhafid MAHROUG , Rabie AMARI , AMMAR Boukhari , A. BENTABET, ,(2018), Experimental and first principles study of structural, electronic and optical properties of Zn0.875Mn0.125O thin film,ICAMS 2018 – 7th International Conference on Advanced Materials and Systems,Bucharest, ROMANIA

The structural, electronic, elastic and optical properties of pure and Mn-doped ZnO with a wurtzite structure were calculated by using first-principles calculation based on density functional theory (DFT) with local density approximation (LDA) [1] plus Hubbard U (DFT–LDA+U) method [2]. This latter represents the theoretical framework to deal with strongly correlated materials to predicted successfully the electronic properties of such materials. The wurtzite ZnO system is then doped with Mn at different sites. The obtained results were discussed and compared with earlier works.

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Bahri DEGHFEL , AMMAR Boukhari , Rabie AMARI , Abdelhafid MAHROUG , A. Bentabet, ,(2017), First principles LDA+U study of structural, electronic, elastic and optical properties of Mn doped wurtzite ZnO.,Nanotechnology and nanomaterials» (NANO-2017),Ukraine - Chernivtsi

Undoped and Al-doped ZnO thin films have been deposited onto glass substrates by the sol–gel spin coating method and their structural and optical properties have been investigated. The XRD results showed that all films were crystallized under hexagonal wurtzite structure and presented a preferential orientation along the c-axis where the maximum crystallite size was found to be 25 nm for undoped film. The average transmittance of all films is over 95% in the visible region and the band gap energy increases from 3.25 to 3.29 eV with the increase of Al concentration. In addition to the vibrational modes from undoped ZnO, longitudinal optical (LO) mode in the Raman spectra was enhanced by the Al doping. Photoluminescence of the films showed an ultraviolet (UV) and defect related visible emissions like violet, blue and green. 3% Al doped ZnO film shows the best photocurrent properties.

Citation

Abdelhafid MAHROUG , SAMIR Hamrit , S. Boudjadar, Lakhdar Guerbous, , (2014), Structural, optical and photocurrent properties of undoped and Al-doped ZnO thin films deposited by sol–gel spin coating technique, Materials letters, Vol:134, Issue:1, pages:248–251, Elsevier

Undoped and Co-doped ZnO thin films with different amounts of Co have been deposited onto glass substrates by sol–gel spin coating method. Zinc acetate dihydrate, cobalt acetate tetrahydrate, isopropanol and monoethanolamine (MEA) were used as a precursor, doping source, solvent and stabilizer, respectively. The molar ratio of MEA to metal ions was maintained at 1.0 and a concentration of metal ions is 0.6 mol L−1. The Co dopant level was defined by the Co/(Co + Zn) ratio it varied from 0 to 7 % mol. The structure, morphology and optical properties of the thin films thus obtained were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDX), scanning electron microscopy (SEM), ultraviolet–visible (UV–Vis), photoluminescence (PL) and Raman. The XRD results showed that all films crystallized under hexagonal wurtzite structure and presented a preferential orientation along the c-axis with the maximum crystallite size was found is 23.5 nm for undoped film. The results of SEM indicate that the undoped ZnO thin film has smooth and uniform surface with small ZnO grains, and the doped ZnO films shows irregular fiber-like stripes and wrinkle network structure. The average transmittance of all films is about 72–97 % in the visible range and the band gap energy decreased from 3.28 to 3.02 eV with increase of Co concentration. DRX, EDX and optical transmission confirm the substitution of Co2+ for Zn2+ at the tetrahedral sites of ZnO. In addition to the vibrational modes from ZnO, the Raman spectra show prominent mode representative of ZnyCo3−yO4 secondary phase at larger values of Co concentration. PL of the films showed a UV and defect related visible emissions like violet, blue and green, and indicated that cobalt doping resulted in red shifting of UV emission and the reduction in the UV and visible emissions intensity.

Citation

Abdelhafid MAHROUG , , (2014), Structural, morphological and optical properties of undoped and Co-doped ZnO thin films prepared by sol–gel process, Journal of Materials Science: Materials in Electronics, Vol:11, Issue:11, pages:2259-2266, Springer

Undoped and Co-doped ZnO thin films with different amounts of Co have been deposited onto glass substrates by sol–gel spin coating method. Zinc acetate dihydrate, cobalt acetate tetrahydrate, isopropanol and monoethanolamine (MEA) were used as a precursor, doping source, solvent and stabilizer, respectively. The molar ratio of MEA to metal ions was maintained at 1.0 and a concentration of metal ions is 0.6 mol L−1. The Co dopant level was defined by the Co/(Co + Zn) ratio it varied from 0 to 7 % mol. The structure, morphology and optical properties of the thin films thus obtained were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDX), scanning electron microscopy (SEM), ultraviolet–visible (UV–Vis), photoluminescence (PL) and Raman. The XRD results showed that all films crystallized under hexagonal wurtzite structure and presented a preferential orientation along the c-axis with the maximum crystallite size was found is 23.5 nm for undoped film. The results of SEM indicate that the undoped ZnO thin film has smooth and uniform surface with small ZnO grains, and the doped ZnO films shows irregular fiber-like stripes and wrinkle network structure. The average transmittance of all films is about 72–97 % in the visible range and the band gap energy decreased from 3.28 to 3.02 eV with increase of Co concentration. DRX, EDX and optical transmission confirm the substitution of Co2+ for Zn2+ at the tetrahedral sites of ZnO. In addition to the vibrational modes from ZnO, the Raman spectra show prominent mode representative of ZnyCo3−yO4 secondary phase at larger values of Co concentration. PL of the films showed a UV and defect related visible emissions like violet, blue and green, and indicated that cobalt doping resulted in red shifting of UV emission and the reduction in the UV and visible emissions intensity.

Citation

SAMIR Hamrit , Abdelhafid MAHROUG , S. Boudjadar, L. Guerbous, , (2014), Structural, morphological and optical properties of undoped and Co-doped ZnO thin films prepared by sol–gel process, Journal of Materials Science: Materials in Electronics, Vol:25, Issue:11, pages:4967–4974, springer