AMMAR Boukhari

CHELALI Wiam Naila

Nanotechnology and nanomaterials

Raid ACHOUCH

CdLiClدراسة الخصائص البنيوية، الإلكترونية والبصرية لمركب 3

Saad RAIS

CdLiFدراسة الخصائص البنيوية، الإلكترونية والضوئية لمركب 3

LEGOUIREH Abderrazak , BOUDJELAL Wail

Scanning Electron Microscopy (SEM)

This investigation explored the structural, thermodynamic and elastic features of two predicted halide perovskites, CdLiF 3 and CdLiCl 3 , using reliable first-principles computations. The relaxed crystalline structures were ascertained utilizing various exchange-correlation functionals. Our results align with previously reported data, particularly when utilizing the GGA-PBE functional. Both compounds analyzed demonstrate considerable thermodynamic and mechanical stability. The study accurately predicts various physical parameters associated with the elasticity characteristics of monocrystalline and polycrystalline forms of the considered materials. CdLiF 3 exhibits greater hardness compared to CdLiCl 3 . Temperature-dependent fluctuations of specific macroscopic physical characteristics, such as lattice parameters, volumetric thermal expansion parameter, Debye temperature and thermal capacity, were assessed using the quasi-harmonic approximation alongside first-principles computations.

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AMMAR Boukhari , Djamel ALLALI , ELHADJ Benrezgua , SABER SAAD ESSAOUD , Rabie AMARI , Bureau de la stratégie de numérisation , Bureau de la stratégie de numérisation , Bureau de la stratégie de numérisation , Bureau de la stratégie de numérisation , Abdelmadjid Bouhemadou,, Abdelhak Bedjaoui, Missoum Radjai, , (2026-01-12), Effects of temperature and pressure on the structural, elastic, and thermodynamic properties of halogenated perovskites CdLiCl 3 and CdLiF 3, International Journal of Modern Physics C, Vol:0, Issue:0, pages:00, World Scientic Publishing Company

This investigation explored the structural, thermodynamic and elastic features of two predicted halide perovskites, CdLiF3 and CdLiCl3, using reliable first-principles computations. The relaxed crystalline structures were ascertained utilizing various exchange-correlation functionals. Our results align with previously reported data, particularly when utilizing the GGA-PBE functional. Both compounds analyzed demonstrate considerable thermodynamic and mechanical stability.The study accurately predicts various physical parameters associated with the elasticity characteristics of monocrystalline and polycrystalline forms of the considered materials. CdLiF3 exhibits greater hardness compared to CdLiCl3. Temperature-dependent fluctuations of specific macroscopic physical characteristics, such as lattice parameters, volumetric thermal expansion parameter, Debye temperature and thermal capacity, were assessed using the quasi-harmonic approximation alongside first-principles computations.

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Rabie AMARI , AMMAR Boukhari , , (2025-12-22), Effects of temperature and pressure on the structural, elastic, and thermodynamic properties of halogenated perovskites CdLiCl3 and CdLiF3, International Journal of Modern Physics C, Vol:0, Issue:1, pages:0, World Scientific Publishing Co. Pte Ltd

We analyzed the structural, elastic, and thermodynamic attributes of the trigonal-type Zintl phases CaZn2Sb2 and SrZn2Sb2 under hydrostatic pressure through using ab initio calculations within the density functional theory framework. The predicted structural parameters agree excellently with the available experimental values, which strongly validate our method. For both of the chemicals investigated, the [001] crystal orientation exhibits a higher compressibility than the [100] direction. Both compounds predicted monocrystalline elastic constants meet the mechanical stability requirements over a pressure range of up to 20 GPa. The polycrystalline mechanical characteristics were also examined at pressures up to 20 GPa. Indicators such as Pugh’s coefficient, Poisson’s ratio and Cauchy pressure confirm the brittleness of the studied compounds. At constant pressures of 0, 5, 10, 15, and 20 GPa, the temperature dependence of important macroscopic physical parameters was studied using the quasiharmonic Debye approximation. These parameters include 2 the lattice parameter, bulk modulus, volumetric thermal expansion coefficient, Debye temperature, and isobaric and isochoric heat capacities. The results are deemed trustworthy because the data acquired from the elastic constants correspond most closely to those calculated from the Debye quasiharmonic approximation.

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Djamel ALLALI , ELHADJ Benrezgua , Rabie AMARI , SABER SAAD ESSAOUD , AMMAR Boukhari , Fares ZERARGA, Abdelhak BEDJAOUI, Missoum RADJAI, ,(2025-11-20), Structural, elastic and thermodynamic characteristics of trigonal-type Zintl phases XZn2Sb2 (X = Ca or Sr) under hydrostatic pressure: Prospects for Advanced Materials in High-Pressure and Thermoelectric Devices,THE 2nd NATIONAL CONFERENCE ON PHYSICS AND IT’S APPLICATIONS,BOUSAADA, ALGERIA

The effect of metal ion (MI) doping on the properties of zinc oxide nanoparticles (ZnO-NPs), was investigated. ZnO-NPs doped with a small amount (1.7 %) of Al, Ag, Cu, and Mn were successfully synthesized. X-ray diffraction (XRD) confirmed the retention of the hexagonal wurtzite structure after doping, with no secondary phases observed. A clear correlation was established between the ionic radii of the dopants and the consistent changes in the structural, vibrational and morphological properties. Ultraviolet–visible (UV–visible) spectroscopy showed a noticeable widening of the optical bandgap, shifting from 3.70 eV (ZnO) to 3.90 eV (Al-doping), 4.04 eV (Ag- doping), 3.88 eV (Cu- doping), and 3.97 eV (Mn- doping).

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Rabie AMARI , Smail TERCHI , Djamel ALLALI , Bahri DEGHFEL , ABDELHAMID Guelil , AMMAR Boukhari , ELHADJ Benrezgua , Abdelhalim Zoukel, Ahmad Azmin Mohamad, , (2025-09-01), The effect of low concentrations of selected metal ions (Al, Ag, Cu, Mn) on the properties of ZnO nanoparticles prepared by the co-precipitation technique, Materials Letters, Vol:394, Issue:, pages:138677, Elsevier, Science Direct

The structural, electronic, and optical characteristics of CdLiF3 and CdLiCl3 halide perovskites were calculated using first-principles calculations based on density functional theory (DFT) employing the generalized gradient approximation (GGA) approach [1,2]. The structural parameters, comprising the lattice constants (a), bulk modulus (B), and its pressure derivative (B'), were computed for the examined compounds. The optimal lattice parameters were a=b=c= 3,699 Å for CdLiF3 and a=b=c= 4.607 Å for CdLiCl3. The electronic band structures and their associated total and partial density of states diagrams were also estimated. The compound CdLiF3 is a semiconductor with a bandgap of 1.96 eV, whereas CdLiCl3 is a semimetal conductor. The spectra of the frequency-dependent complex dielectric function, absorption coefficient, refractive index, extinction coefficient, reflectivity, and electron energy loss function were computed and analyzed.

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AMMAR Boukhari , Rabie AMARI , ELHADJ Benrezgua , Djamel ALLALI , Bahri DEGHFEL , ,(2025-08-20), Structural, electronic and optical properties of CdLiF3 and CdLiCl3 halide perovskites using first-principles calculation,INTERNATIONAL RESEARCH AND PRACTICE CONFERENCE “NANOTECHNOLOGY AND NANOMATERIALS”,Bukovel, UKRAINE

This study aims to prepare manganese-doped zinc oxide (MZO) thin films with low Mn content (x = 0, 2, 4 %) using the sol–gel spin coating method and to characterize their structural, optical, and magnetic properties. Experimental techniques were complemented by Density Functional Theory calculations with Hubbard correction (DFT-LDA + U). All films exhibit a polycrystalline wurtzite hexagonal phase of ZnO. As the Mn doping increases, all diffraction peaks are getting weaker, which leads to deterioration in the crystallinity of the samples. Furthermore, Mn doping affects the grain size (57.44–38.20 nm), the surface morphology (rms: 45.24–30.47 nm), the transmittance (93–54 %) and the optical band gap energy (Eg: 3.27–3.18 eV). Photoluminescence spectra reveals ultraviolet peaks (386–395 nm) along with weak green (525 nm) and strong (438 nm) and weak (475 nm) blue peaks. DFT-LDA + U calculations exhibits an antiferromagnetic phase with slightly reduced Eg (3.379 eV for x = 0 % and 3.267 for 3.7 %), attributed to the influence of Mn3d states near the Fermi level. This study presents a comprehensive analysis of low-content Mn-doped ZnO thin films by combining experimental and theoretical approaches. The findings provide valuable insights into the electronic, structural, optical, and magnetic properties of MZO, emphasizing the critical role of Mn 3d states in altering the magnetic behavior and adjusting Eg.

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ELHADJ Benrezgua , Rabie AMARI , AMMAR Boukhari , Djamel ALLALI , Smail TERCHI , Bahri DEGHFEL , ABDELHAMID Guelil , Abdelhalim Zoukel, Ahmad Azmin Mohamad, , (2025-02-01), Synthesis of low-content Mn-doped ZnO thin films: Characterizations and density functional theory studies, Inorganic Chemistry Communications, Vol:172, Issue:172, pages:113710, Elsevier, Science Direct

This study investigates copper oxide thin films synthesized via the sol-gel method and deposited onto glass substrates using spin coating. The aim was to enhance their properties for photovoltaic applications through optimization of annealing temperature and precursor solution molar concentration. We examined the effects of annealing temperature on the structural and optical properties [1, 2] of the films. Notably, films treated at 450°C exhibited increased absorbance. Subsequently, employing this optimized temperature, CuO thin films of varying molar concentrations were deposited under the same conditions. Structural analysis via X-ray diffraction revealed a polycrystalline nature with a monoclinic crystal structure for all samples. Optical characterization using UV-Visible-NIR spectrophotometry indicated high absorbance in the visible region for the films.

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Djamel ALLALI , Rabie AMARI , AMMAR Boukhari , ELHADJ Benrezgua , Chouia Rabah, ,(2024-05-06), Study of Structural and Optical Properties of Copper Oxide Thin Films Prepared by Sol–Gel Spin–Coating Method,Le 2ème colloque national de chimie (CNC2@2024) 6 - 7 mai 2024,Msila

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

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

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

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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

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.

Citation

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