AMMAR Boukhari

LEGOUIREH Abderrazak , BOUDJELAL Wail

Scanning Electron Microscopy (SEM)

In this work, the Cambridge Serial Total Energy Package CASTEP within Density Functional Theory (DFT) is used to study the structural and electronic properties of cubic silver based perovskite AgXCl3 (X= Be; space group pm-3m (221)). The structural investigation reveals the stability of these compounds. The band structure and density of states indicates the semiconducting nature of the compound.The study reveals the potential as candidates for optoelectronic devices.

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AMMAR Boukhari , Rabie AMARI , Djamel ALLALI , Bahri DEGHFEL , ,(2023-12-02), Structural and electronic properties of AgBeCl3 Perovskites: DFT based First-principles calculations,THE 1ST NATIONAL CONFERENCE ON PHYSICS AND IT’S APPLICATIONS,BOUSAADA

The study successfully produced ZnO and ZnO nanoparticles doped with transition metals (TMZO-NPs) using the coprecipitation method. Various properties of these nanoparticles were examined, including their structure, morphology, electronic behavior, optical characteristics, vibrations, and photocatalytic abilities. The analysis confrmed that all nanoparticles possessed a hexagonal wurtzite crystalline structure, with particle size being infuenced by the presence of transition metals (Al, Ag, Cu, Mn). The particles exhibited a preference for orientation along the (002) axis. The shift in peak positions towards higher angles suggested that the TM might replace Zn ions in the ZnO lattice. The surface structure of the nanoparticles displayed a combination of spherical and hexagonal shapes. Further analysis identifed important bands related to the stretching modes of TM-O and Zn–O bonds. The absorption properties and edges were also afected by the presence of TM. In the degradation study, both pure ZnO and TMZO-NPs were tested for their ability to break down methylene blue (MB) under UV light exposure for 90 min. Among the nanoparticles, Al-doped ZnO (AlZO-NPs) demonstrated the highest degradation efciency, achieving 97.14% removal of MB within the given exposure time. The photocatalytic process followed a pseudo-frst-order kinetics, indicating a strong correlation. This suggests that AlZO-NPs hold promise as a material for use in photocatalytic applications.

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AMMAR Boukhari , , (2023-11-24), Coprecipitation synthesis of transition metal (Al, Mn, Cu, Ag) doped zinc oxide nanopowders: characterization, photocatalytic test, and comparison study, Journal of the Australian Ceramic Society, Vol:2023, Issue:2023, pages:1-10, Springer Nature Singapore

The present research utilizes ab initio computations to examine the thermodynamic, structural, and elastic characteristics of XAgO ternary oxides, where X signifies Li, Na, K, and Rb.The GGA-PBE and GGA-WC functionals were used to calculate the ground-state lattice parameters and atomic position coordinates of the title materials. The calculated results were in good agreement with both experimental measurements and theoretical predictions. This suggests that the GGA-PBE and GGA-WC functionals are accurate for describing the structural properties of the material under study.This study offers computational predictions for the elastic properties of monocrystalline structures and polycrystalline aggregates of XAgO compounds. These predictions encompass various key parameters, including single-crystal elastic constants, Young's modulus, bulk modulus, Lame coefficients, Poisson's ratio, shear modulus, and Debye temperature. Additionally, the quasi-harmonic Debye approximation is utilized to explore the temperature-dependent behavior of bulk modulus, Debye temperature, volume thermal expansion coefficient, and isobaric and isochoric heat capacities over an extensive temperature range, while maintaining constant pressures. The results obtained from this model are found to be highly successful in accurately predicting the behavior of these properties.

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Djamel ALLALI , Rabie AMARI , AMMAR Boukhari , Bahri DEGHFEL , SABER SAAD ESSAOUD , Abdelmadjid Bouhemadou, Saad Bin-Omran, Missoum Radjai, Rabah Khenata, Yarub Al-Douri, , (2023-10-04), Ab initio investigation of structural, elastic, and thermodynamic characteristics of tetragonal XAgO compounds (X = Li, Na, K, Rb), Physica Scripta, Vol:98, Issue:11, pages:115905, IOPscience

The present research utilizes ab initio computations to examine the thermodynamic, structural, and elastic characteristics of XAgO ternary oxides, where X signifies Li, Na, K, and Rb.The GGA-PBE and GGA-WCfunctionals were used to calculate the ground-state lattice parameters and atomic position coordinates of the title materials. The calculated results were in good agreement with both experimental measurements and theoretical predictions. This suggests that the GGA-PBE and GGAWCfunctionals are accurate for describing the structural properties of the material under study.This study offers computational predictions for the elastic properties of monocrystalline structures and polycrystalline aggregates of XAgO compounds. These predictions encompass various key parameters, including single-crystal elastic constants, Young’s modulus, bulk modulus, Lame coefficients, Poisson’s ratio, shear modulus, and Debye temperature. Additionally, the quasi-harmonic Debye approximation is utilized to explore the temperature-dependent behavior of bulk modulus, Debye temperature, volume thermal expansion coefficient, and isobaric and isochoric heat capacities over an extensive temperature range, while maintaining constant pressures. The results obtained from this model are found to be highly successful in accurately predicting the behavior of these properties.

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Djamel ALLALI , AMMAR Boukhari , Rabie AMARI , Bahri DEGHFEL , SABER SAAD ESSAOUD , Bouhemadou Abdelmadjid, , (2023-10-04), Ab initio investigation of structural, elastic, and thermodynamic characteristics of tetragonal XAgO compounds (X = Li, Na, K, Rb), Physica scripta, Vol:98, Issue:, pages:115905, IOPscience

In the present study, transition metal Al-doped ZnO nanoparticles (TM-ZN NPs) were synthesized via the chemical co-precipitation method. The structural, morphological, electronic, optical, vibrational as well as the photocatalytic properties of the elaborated TMZO-NPs, are then investigated. Hexagonal wurtzite crystallinity of all elaborated NPs is confirmed by the phase analysis and particle size is found to be affected by TM doping. XRD peak shows that all samples prefer orientation along (002) axis and TM (Al) may substitute ZnO structure as the peaks shift toward higher angles. The surface morphology of all samples exhibits mixture of spheroid-like and hexagon-like shaped structures. FTIR analyses are carried out to identify the important bands attributed to TM-O and Zn-O stretching vibration modes. The absorption intensity and edge are found affected by adding TM dopant. Degradation by pure ZnO and TMZO NPs of the methylene blue is investigated after 90 min UV light exposure. TM dopant affects the degradation of MB dye, where a high percentage (97.14%) being achieved after reasonable time of exposure (90 min) under UV light for Aluminum doped ZnO nanoparticles (AlZO NPs).

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Rabie AMARI , ELHADJ Benrezgua , Bahri DEGHFEL , AMMAR Boukhari , Djamel ALLALI , Siassi A, ,(2023-08-16), Studies on photocatalytic performance applications of undoped and Al-doped ZnO nanoparticles,NANO-2023,Bukovel, UKRAINE

In this study, we conducted an ab initio investigation of the structural, electronic and optical properties of AgCaBr3 and AgSrBr3 Calcium-based halide perovskites. using the full-potential linearized augmented plane-wave (FP-LAPW+lo) method [1] basis set as implemented in the WIEN2k code [2].Calculated structural parameters, including the lattice constants (a), bulk modulus (B) and its pressure derivative (B'), for the considered compounds using both the local density (LDA) [3] and generalized gradient approximations (GGA–PBEsol) [4] are consistent with the available data in the scientific literature. To calculate the electronic properties, the exchange-correlation potential is treated with various functionals, and we find that the newly developed Tran–Blaha-modified Becke–Johnson (TB-mBJ) [5–7] functional significantly improves the band gap. Band structure, total and site-projected l-decomposed densities of states, charge-carrier effective masses, charge transfers and charge density distribution maps were obtained; analyzed and compared with the available theoretical data. The frequency-dependent complex dielectric function, absorption coefficient, refractive index, extinction coefficient, reflectivity and electron energy loss function spectra were calculated. The origins of the peaks and structures in the optical spectra are determined in terms of the calculated energy band structures.

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Djamel ALLALI , Rabie AMARI , Bahri DEGHFEL , AMMAR Boukhari , ,(2023-08-16), Electronic and optical properties of of AgXBr3 (X = Ca and Sr) Perovskites: An ab initio study with the Tran–Blaha-modified Becke–Johnson density functional,NANO-2023,Bukovel, UKRAINE

In this study, we conducted an ab initio investigation of the structural, elastic, electronic and optical properties of AgCaBr 3 and AgCaF 3 Calcium-based halide perovskites. Our findings suggest that these materials exhibit a high degree of stability in the cubic structure, with optimized lattice parameters that agree well with previous theoretical predictions. We estimated the monocrystalline elastic constants (C ij ) for these compounds via the strain-stress method. Using the predicted C ij values, we were able to deduce various elastic moduli for AgCaBr 3 and AgCaF 3 polycrystalline aggregates, including bulk modulus, Young's modulus, shear modulus, Lame coefficients, Poisson's ratio, and Debye temperature. Band structure, density of states and band gap pressure coefficients are also given. Our calculations show that AgCaBr 3 and AgCaF 3 has an indirect band gap (R–Γ). We present calculations of the frequency-dependent complex dielectric function . We find that the values of zero-frequency limit increase with decreasing the energy band gap. The origin of the peaks and structures in the optical spectra is determined in terms of the calculated energy band structures. We hope that our study provides valuable insights into the structural, elastic, electronic and optical properties of AgCaX 3 perovskites compounds that may be reference data for future investigations of these materials.

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AMMAR Boukhari , ,(2023-06-16), AN AB INITIO STUDY OF THE STRUCTURAL, ELASTIC, ELECTRONIC AND OPTICAL PROPERTIES OF AgCaX3 (X = Br, and F) PEROVSKITES,the 4. INTERNATIONAL MEDITERRANEAN CONGRESS,Cyprus Nicosia, TRNC

Nanoparticles (NPs) synthesized by the co-precipitation technique show many attractive properties such as small particle size, high crystallinity, high average pore diameter and high specific surface area. However, numerous reports show that some characteristics of the Ni-doped ZnO (NZO) NPs remain controversial such as optical bandgap (Eg), surface morphology and defect level. In this study, pure ZnO and NZO NPs at different Ni contents (x) were successfully prepared using the co-precipitation method. Phase analysis confirms the hexagonal wurtzite crystallinity of the samples. XRD peak shows that the Ni may substituted ZnO structure as the peaks shift toward higher angles with increasing x. Meanwhile, the formation of NiO secondary phases was significant at 12.50% Ni content. Densely packed spherical shaped structures with nanoparticle agglomeration are observed at low x, while some nanorod shaped structures appear at higher x. The stretching vibrations of the Zn–O bond are observed in the NZO NPs. The absorption edge shifts to higher wavelengths with the increase in x. This study provides consistent results in the phase analysis, morphology and structural parameters. The decrease in Eg agrees with the photoluminescence measurements. The emission spectra confirm the presence of interstitial zinc and singly ionized oxygen vacancies.

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Rabie AMARI , ELHADJ Benrezgua , Bahri DEGHFEL , AMMAR Boukhari , Zoukel Abdelhalim, Mohamad kamil Yaakob, wan Jeffrey bassirun, Soorathep Kheawhom, Ahmad Azmin Mohamad, , (2022), Ni doping effect on the electronic, structural and optical properties of ZnO nanoparticles prepared by Co-precipitation route, Optical Materials, Vol:128, Issue:, pages:112398, Elsevier

Numerous studies on Cu-doped ZnO (CZO) thin film doped as a p-type material have been reported due to its applications in optoelectronic and gas sensing devices. The synthesis and fabrication of CZO thin films by various techniques have been reported, but the sol-gel technique for both spin and dip coating has attracted much attention due to its safety, low cost and simple deposition equipment on a large surface-area. Motivated by the fact that reviews on CZO thin films have not been reported yet, this review summarizes the main chemical processes used in the fabrication of CZO thin films with special focus on the sol-gel synthesis involving several chemical and physical parameters such as solvent, additive, solution stirring and aging time, substrate and coating method which includes both dip and spin coating. It also highlights the various parameters influencing the structural, morphological, electronic, optical, vibrational and magnetic properties of the CZO thin films. For this purpose, a summary of various parameters of CZO thin films, reported in the literature survey of the past ten years (2010–2020), is tabulated and discussed. The influence of Cu doping on the synthesis and properties of CZO thin films is also reviewed. The structural, electronic, optical, magnetic and vibrational properties, as well as the elemental composition and surface morphology of the CZO thin films are also discussed. At the end of this review, an outlook is presented to gain more insights into the combined effects of the method-preparation-dopant combination on the properties of CZO thin films for future potential applications. This review should be a useful benchmark for researchers to explore the various physicochemical properties of CZO, their dependence on the experimental conditions and applications.

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ELHADJ Benrezgua , Bahri DEGHFEL , Rabie AMARI , AMMAR Boukhari , Zoukel Abdelhalim, Wan Jeffrey Basirun, Muhamad Kamil Yaakob, Soorathep kheawhom, Ahmad Azmin Mohamad, , (2022), Synthesis and properties of copper doped zinc oxide thin films by sol-gel, spin coating and dipping: A characterization review, Journal of Molecular Structure, Vol:1267, Issue:, pages:133639, Elsevier

Some efforts have been made on Cu-doped ZnO (CZO) structures to study the electronic, structural, magnetic and optical properties from first-principles calculations by different computer codes. This is very interesting to review in detail about CZO structures. A summary of the convergence criteria of geometry optimization for CZO structures from the literature survey (2010–2021) is tabulated and discussed. The impact of the Hubbard-U scheme in the exchange-correlation functional on the standard Density Functional Theory (DFT) miscalculation for CZO properties is comprehensively reviewed. The inclusion of Ud-Zn, Ud-Cu and Up-O all to gather leads to a correct energy band gap, and exhibits a slight effect on the lattice constant. The values of Ud-Zn, Ud-Cu and Up-O have a considerable impact on the intensity and position of the main peaks of the imaginary part. The magnetic phase of the CZO structure is found to be influenced by both Ud,Zn and Ud,Cu. More attention is paid to the influence of Cu doping content on CZO properties, including electronic, structural, optical and magnetic properties. The magnetic moment mainly comes from Cu ions with little contribution from O ions. Ferromagnetic (FM) spin ordering of Cu ions are suggested to be mediated by the holes induced in p-d hybridization. Finally, some perspectives for future studies are discussed as well.

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ELHADJ Benrezgua , Bahri DEGHFEL , AMMAR Boukhari , Rabie AMARI , Abdelhalim Zoukel, Soorathep kheawhom, Ahmad Azmin Mohamad, , (2022), A Review on DFT+ U Scheme for Structural, Electronic, Optical and Magnetic Properties of Copper Doped ZnO Wurtzite Structure, Materials Today Communication, Vol:31, Issue:, pages:103306, Elsevier

Ab initio full-potential (linearized) augmented plane-wave plus local orbitals (FP-(L)APW+lo) structural, electronic, magnetic and optical properties of MgFe2O4 compound. The calculated equilibrium structural parameters using both the local density approximation and the generalized gradient approximation are well consistent with the available theoretical and experimental data in the literature. Furthermore, band structure calculations demonstrate that MgFe2O4 compound exhibits large band gaps in both spins configurations with large magnetic moment. Energetically, Ferrite nickel favors the inverse spinel phase in which Fe and Mg cations in either octahedral or tetrahedral sites adopt the high spin configuration. We found that energy of the normal spinel is higher than that of the inverse spinel confirming that inverse spinel is the most stable structure of MgFe2O4 compound. The optical behavior of MgFe2O4 compound is characterized by calculating the real and imaginary part of the dielectric function, the absorption coefficients, the refractive index, the optical conductivity and the energy loss. Optimizing structural, electronic, magnetic and optical properties of this novel compound is crucial for exploring and utilizing it for modern device applications

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AMMAR Boukhari , ,(2022), Electronic structure, magnetic and optic properties of spinel compound MgFe2O4,First International Conference on Materials Sciences and Technology,Abbes LAGHROUR University, Khenchela, Algeria

In this work, 8.5% Cu-doped ZnO thin film was fabricated on glass substrate using sol–gel spin coating method, in order to investigate the structural, optical and morphological properties. XRD result exhibited 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 74.68% in the visible range. The optical band gap energy was found to be 3.317 eV. The surface morphology showed a mixer of spheroid-like and rod-like nanoparticles (granules) randomly distributed.

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AMMAR Boukhari , ELHADJ Benrezgua , Rabie AMARI , Djamel ALLALI , Bahri DEGHFEL , ,(2022), Structural, morphological and optical properties of Cu-doped ZnO thin films prepared by sol-gel spin coating method,1st international conference on chemical matters and environment preservation IC-CMEP’22,Ouargla, Algeria

In this work, pure and Ni-doped ZnO nanoparticles (NPs) with concentration of Ni (6.25%) were successfully prepared by using co-precipitation method [1]. Among TM, nickel is very significant element which has a similar ionic radius as that of Zn. Literature studies show that Ni doping into ZnO matrix can enhance its various properties [2, 3]. Zinc acetate dihydrate [Zn (CH3COO)2 2H2O], nickel acetate dihydrate [Ni (CH3COO)2 2H2O] and sodium hydroxide solution [NaOH] were used as precursors. For getting homogeneous solution, stoichiometric amount of zinc and nickel acetate were dissolved in methanol, after stirred continuously on a magnetic stirrer at room temperature. For raising the pH of the obtained solution to ~9, small amount of sodium hydroxide solution [NaOH] was added drop by drop. The precursor solution is then stirred again until the liquid solution turns into a gel. After gel formation, the beaker was transferred on the hot plate at 500°C for 1h. The obtained sample yield in the form of loose powder was then finely grounded by agate mortar and pestle. The prepared samples in powder form were characterized by X-ray diffraction spectroscopy (XRD), Scanning Electron Microscopy (SEM), Ultraviolet–visible spectroscopy (UV-Vis), Photoluminescence (PL) and Fourier transform infrared spectroscopy (FTIR). The obtained results have been discussed and compared with those from other sources whatever possible.

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Rabie AMARI , ELHADJ Benrezgua , Bahri DEGHFEL , AMMAR Boukhari , ,(2022), Studies on structural, morphological, optical, luminescence and electronic properties of Ni-doped ZnO nanopowder by co-precipitation method,1st international conference on chemical matters and environment preservation IC-CMEP’22,Ouargla, Algeria

We report ab initio density functional theory calculations of the structural, electronic and optical properties of Ag-based ternary oxides XAgO (X= Li and Na) using the full-potential linearized augmented plane-wave (FP-LAPW+lo) method [1] basis set as implemented in the WIEN2k code [2]. Calculated structural parameters, including the two lattice constants, (a) and (c), three internal coordinates, yX, xAg, and xO, bulk modulus (B) and its pressure derivative (B'), for the considered compounds using both the local density (LDA) [3] and generalized gradient approximations (GGA–PBEsol) [4] are consistent with the available data in the scientific literature. To calculate the electronic properties, the exchangecorrelation potential is treated with various functionals, and we find that the newly developed Tran–Blaha-modified Becke–Johnson (TB-mBJ) [5–7] functional significantly improves the band gap. Band structure, total and site-projected l-decomposed densities of states, charge-carrier effective masses, charge transfers and charge density distribution maps were obtained; analyzed and compared with the available theoretical data. The frequency-dependent complex dielectric function, absorption coefficient, refractive index, extinction coefficient, reflectivity and electron energy loss function spectra were calculated with an incident radiation polarized parallel to both [100] and [001] crystalline directions. The origins of the peaks and structures in the optical spectra are determined in terms of the calculated energy band structures

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Djamel ALLALI , AMMAR Boukhari , Rabie AMARI , Fares ZERARGA, Abdelmadjid BOUHEMADOU, Khadidja BOUDIAF, ,(2022), Electronic and optical properties of Ag-based oxides XAgO (X= Li and Na): An ab initio study with the Tran–Blahamodified Becke–Johnson density functional,1st international conference on chemical matters and environment preservation IC-CMEP’22,Ouargla, Algeria

The first-principles method based on DFT with semiempirical Hubbard U scheme was applied to calculate the structural, elastic, electronic, and optical properties of ZnO wurtzite material. The effective Hubbard U values of 5.5 eV and 8 eV were used for Zn 3d and O 2p states, respectively. Electronic band structures and their corresponding total and partial density of states diagram were calculated. The optimized lattice parameters were a=b= 3,234 Å and c= 5,201 Å. The elastic stiffness constants of ZnO crystals were estimated from the optimized structure. The obtained band gap was found 3.38 eV. The frequency-dependent complex dielectric function, absorption coefficient, refractive index, extinction coefficient, reflectivity and electron energy loss function spectra were also calculated and discussed.

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AMMAR Boukhari , Rabie AMARI , ELHADJ Benrezgua , Bahri DEGHFEL , ,(2022), Structural, electronic, optical and elastic properties of pure ZnO material using first-principles calculation,The first national Seminar on Green Chemistry and Natural Products (GCNP’22),University of Echahid Hamma Lakhdar, El-Oued

The present work studied the structural and luminescence properties of 10% Mn-doped ZnO thin film fabricated on glass substrate using sol–gel spin coating method. XRD result exhibited 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 55% in the visible range. The optical band gap energy was found to be 3.19 eV. The surface morphology showed a mixer of spheroid-like and rod-like nanoparticles (granules) randomly distributed. Photoluminescence (PL) spectra shows several emission bands, including one violet emission (defect) at 411 nm (~3.01 eV), two blue emissions at 438/475 nm (~2.83/~2.61 eV), and weak green emission at 525 nm (~2.36 eV).

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ELHADJ Benrezgua , Rabie AMARI , AMMAR Boukhari , Bahri DEGHFEL , ,(2022), Structural, electronic, morphological and luminescence properties of 10% Mn-Doped ZnO Thin Films,The first national Seminar on Green Chemistry and Natural Products (GCNP’22),University of Echahid Hamma Lakhdar, El-Oued

In this study, 10.8% Cu-doped ZnO thin film was deposited on glass substrate using sol–gel spin coating technique, in order to investigate the structural, optical and morphological properties. XRD result exhibited 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 80% in the visible range. The optical band gap energy was found to be 3.25 eV. The surface morphology showed a mixer of spheroid-like and rod-like nanoparticles (granules) randomly distributed.

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Rabie AMARI , ELHADJ Benrezgua , AMMAR Boukhari , Bahri DEGHFEL , ,(2022), Structural, Optical and Morphological properties of 10.8% Cu-Doped ZnO Thin Films,The first national Seminar on Green Chemistry and Natural Products (GCNP’22),University of Echahid Hamma Lakhdar, El-Oued

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Rabie AMARI , Djamel ALLALI , Bahri DEGHFEL , ELHADJ Benrezgua , AMMAR Boukhari , ,(2022), Experimental and first principles study of structural, electronic and optical properties of Zn0.875Mn0.125O nanoparticles by co-precipitation method,10th International Conference on Materials Sciences And Technology, (MatScience-2022),khenchela, Algeria

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AMMAR Boukhari , ,(2022), Theoretical and experimental study of structural, electronic and optical properties of Al doped ZnO nanoparticles by co-precipitation method,10th International Conference on Materials Sciences And Technology, (MatScience-2022),khenchela, Algeria

Structural parameters, elastic constants and thermodynamic properties of the tetragonal ternary Ag-based oxides LiAgO and NaAgO are investigated theoretically for the first time using the plane-wave ultra-soft pseudopotential method [1] based on the density functional theory [2,3]. The optimized lattice parameters and atomic positions agree well with the available theoretical and experimental counterparts. Pressure dependence of the structural parameters is also explored. Pressure dependences of the single-crystal elastic constants Cij for LiAgO and NaAgO are explored. The elastic wave velocities propagating along the principal crystallographic directions are numerically estimated. The elastic anisotropy is estimated and further illustrated by 3D-direction-dependent of the Young’s modulus. A set of some macroscopic elastic moduli, including the bulk, Young’s and shear moduli, Poisson’s coefficient, average elastic wave velocities and Debye temperature, were calculated for polycrystalline LiAgO and NaAgO from the Cij via the Voigt-Reuss-Hill approximations [4–6]. Through the quasiharmonic Debye model [7], which takes into account the phonon effects, the temperature and pressure dependencies of the bulk modulus, unit cell volume, volume thermal expansion coefficient, Debye temperature and volume constant and pressure constant heat capacities of LiAgO and NaAgO are explored systematically in the ranges of 0–20 GPa and 0–1200 K.

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Djamel ALLALI , Amari Rabie , Bahri DEGHFEL , AMMAR Boukhari , ,(2022), Structural, elastic and thermodynamic properties of Ag-based oxides XAgO (X = Li and Na): An ab initio study,10th International Conference “Nanotechnologies and Nanomaterials” (NANO-2022),Lviv. Ukraine

Pure and Ni-doped ZnO nanoparticles (NPs) with concentration of Ni (12.5%) were successfully prepared by using co-precipitation method [1]. Among TM, nickel is very significant element which has a similar ionic radius as that of Zn. Literature studies show that Ni doping into ZnO matrix can enhance its various properties [2, 3]. The prepared samples in powder form were characterized by X-ray diffraction spectroscopy (XRD), Scanning Electron Microscopy (SEM), Ultraviolet–visible spectroscopy (UV-Vis), Photoluminescence (PL) and Fourier transform infrared spectroscopy (FTIR). The obtained results have been discussed and compared with those from other sources whatever possible.

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Rabie AMARI , ELHADJ Benrezgua , Djamel ALLALI , Bahri DEGHFEL , AMMAR Boukhari , ,(2022), Effect of high Ni Doping on the properties of ZnO Nanopowders,10th International Conference “Nanotechnologies and Nanomaterials” (NANO-2022),Lviv. Ukraine

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

The structural, morphological, electronic, and optical properties of pure, 4 %, and 7 % Mn-doped ZnO thin films deposited on glass substrate by the sol–gel spin coating process are investigated in this study. All films exhibited a hexagonal wurtzite structure with a strong c-axis preference. The surface morphology was uniform, with a cracks and wrinkles. With increasing thickness, the transmittance decreased. The bandgap energy varied inversely with the coatings number. photoluminescence spectra revealed ultraviolet with strong and weak blue emission peaks, as well as weak green emission peaks. The structural, electronic, and optical properties of pure and 6.25 % Mn-doped ZnO materials were then investigated using density functional theory and the Hubbard (DFT+U) approach. The DFT+U approach demonstrated a decrease in bandgap energy from pure to 6.25 % Mn-doped ZnO material. It was also discovered that the Mn3d states were distributed far from the Fermi level, with both ionic and covalent nature bonds coexisting. Mn doping caused a small shift in optical properties toward the lower energy. The theoretical findings were consistent with those obtained through experiment

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AMMARBoukhari , ,(2021); Elaboration, characterization and modeling of oxide-based nanostructured thin films,University of M'sila,

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, 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

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

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AMMAR Boukhari , ,(2017), Elaboration and Characterization of TM-doped ZnO Thin Films: Effect of doping on structural and optical properties.,Nanotechnology and nanomaterials» (NANO-2017),Ukraine - Chernivtsi

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

Cr/Si bilayers were irradiated at room temperature with 120 keV Ar, 140 keV Kr and 350 keV Xe ions to fluences ranging from 1015 to 2 × 1016 ions/cm2. The thickness of Cr layer evaporated on Si substrate was about 400 Å. Rutherford backscattering spectrometry (RBS) was used to investigate the atomic mixing induced at the Cr–Si interface as function of the incident ion mass and fluence. We observed that for the samples irradiated with Ar ions, RBS yields from both Cr layer and Si substrate are the same as before the irradiation. There is no mixing of Cr and Si atoms, even at the fluence of 2 × 1016 ions/cm2. For the samples irradiated with Kr ions, a slight broadening of the Cr and Si interfacial edges was produced from the fluence of 5 × 1015 ions/cm2. The broadening of the Cr and Si interfacial edges is more pronounced with Xe ions particularly to the fluence of 1016 ions/cm2. The interface broadening was found to depend linearly on the ion fluence and suggests that the mixing is like a diffusion controlled process. The experimental mixing rates were determined and compared with values predicted by ballistic and thermal spike models. Our experimental data were well reproduced by the thermal spikes model.

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AMMAR Boukhari , Said Tobbeche, Rachid Khalfaoui, A.Amokrane, Chawki Benazzouz, Abderrahim Guittoume, , (2011), Mixing of Cr and Si atoms induced by noble gas ions irradiation of Cr/Si bilayers, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol:269, Issue:24, pages:3242-3245, North-Holland