Publications Internationales
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Item Synthesis and Characterization of Twin Barrel-Like Tungsten Trioxide Obtained by Hydrothermal Treatment(Pleiades Publishing, 2025) Amokrane, Sonia; Hamidouche, Fahim; Irekti, Amar; Saadi, Souad; Meguellati, Zineb; Bouguerra, Kaouthar; Hammadou, Souad née MesdourVarious methods have been presented lately in literature for the elaboration of tungsten oxide (WO3) materials. Herein, WO3 was prepared under properly controlled conditions by hydrothermal route, using Na2WO4·2H2O as a raw material in the presence of different structure directing agents (SDAs) and by acidifying the medium with nitric acid to pH 1. The influence of the SDAs on the structure and morphology of the obtained tungsten oxide has been investigated by scanning electron microscopy (SEM), micro-Raman spectroscopy and X-ray powder diffraction. The obtained WO3 materials have a barrel-like morphology independently of the SDA used. However the crystalline structure obtained is a pure hexagonal WO3 with CoSO4·7H2O, CuSO4·5H2O, ZnSO4·7H2O and Zn(CH3COO)2·2H2O and a hydrated hexagonal WO3: WO3·1/3H2O with MnCl2·4H2O. The results demonstrate a noteworthy effect of the SDA anion on the crystalline structure of the synthesized tungsten oxide as compared to the minor effect from the cation of the SDA. Furthermore, a formation mechanism of the nanobarrel WO3 is proposedItem Montmorillonite/Poly(Pyrrole) for Low-Cost Supercapacitor Electrode Hybrid Materials(MDPI, 2024) Hamidouche, Fahim; Ghebache, Zohra; Lepretre, Jean-Claude; Djelali, Nacer-EddineConductive polymers such as polypyrrole have been widely used as pseudo-capacitive electrodes for supercapacitors. This work demonstrates a simple method to improve the performance of conductive polymer electrodes by adding montmorillonite in order to perform capacitive behavior. Conductive composite polymers (CCPs) based on montmorillonite/polypyrrole (MMT/PPy(Cl)) have been synthesized by polymerization using FeCl3 as an oxidizing agent. During the preparation of CCP, the effect of MMT/pyrrole mass ratio and the influence of the amount of added H+ and temperature of the synthesis medium on the electrochemical performance of the composite have been investigated. The investigation associated with conductivity measurement allowed us to determine the best conditions to reach a high specific capacitance of 465 F gr−1 measured by cyclic voltammetry with respect to the CCP synthesized at ambient temperature (220 F gr−1) and a 35% increase in capacity compared to its homologue synthesized in neutral conditions at a low temperature. These performances have been advantageously correlated both to the edge acidity of the host material and to the evolution of its conductivity according to the preparation conditions. The galvanostatic charge/discharge tests also confirm the stability of the obtained composite, and a capacitance of 325 F g−1 for the best CCP is recorded with a regime of 1 A g−1. In addition, the durability of the device shows that the proposed material has a relatively good stability during cycling.Item Catalytic Activity of Phenol Oxidation over Iron and Cooper-Exchanged Pillared Bentonite(Springer Nature, 2024) Chellal, Khalida; Hamidouche, Fahim; Boudieb, Naima; Meguellati, Zineb; Trari, MohamedAl, mixed Al–Fe and Al–Cu pillared clays were prepared by the conventional method in a diluted medium with two additional parameters for the synthesis; the first one is the cooling of the clay suspension and the second is the exchange between the clay and metal solutions before pillaring with the polymeric mixed solution. The solids were characterized by X-ray diffraction (XRD), N2 adsorption and H2-TPR. The effects of the atomic ratio (M/Al + M) and hydrolysis molar ratio (OH/M), on the basal spacing and/or the specific surface were examined. The exchange does not seem to fix more Cu as in the case of Fe. The dispersion of the cold clay suspension, before pillaring, leads to a greater basal spacing of the solid at room temperature. In the case of mixed Al–Fe exchanged and/or pillared clays calcined at 350 °C, the cold dispersion of the clay suspension increases the basal spacing from 15.89 to 17.44 Å and from 15.32 to 16.07 Å for MR-AlFe (10) and Fe/MR-AlFe (10) respectively. Catalytic Wet Peroxide Oxidation (CWPO) of phenol under mild conditions (25 °C, 1 atm) was carried out without correction of pH. Mixed Al–Fe and Al–Cu pillared clays have comparable performances, although they showed some differences in the H2O2 decomposition kinetics. A total conversion of H2O2 is obtained without the complete phenol conversion over mixed Al–Fe pillared clays suggesting the presence of active species in these catalysts. In a slight excess of H2O2, the activity increases for all Fe-based clays catalysts with increasing the Fe content. A total conversion of phenol was obtained within 15 h of reaction over Fe/MR-AlFe (10) and after extending the reaction time to 30 h in the presence of Fe/MR-Al. On the contrary, MR-AlFe (10) only converted 57.12% under the same conditions. MR-AlFe (10) has the greater basal space (17.44 Å) and is more active for H2O2 decomposition than Fe/MR-Al, which certainly allowed greater accessibility of the reactant to the Fe-species. Fe exchanged and post-pillared clay with mixed (Al–Fe) solution containing 10% Fe expressed as molar percentage {Fe/MR-AlFe (10)} was the most efficient for this reaction combining good catalytic activity with high stability against iron leaching (0.02%). It showed a total phenol degradation, the highest H2O2 decomposition (85.7%) and more than 80% of TOC removal after 15 h of reaction.Item Study of the Influence of Metal Surface Quality on the Performance of an Epoxy Coating(Elsevier, 2023) Boudieb, Naima; Bounoughaz, Moussa; Hamidouche, Fahim; Ghebache, ZohraIn the present work, an EC used for steel corrosion protection was characterized by Ec techniques. This study aimed to describe the effect of the steel roughness surface on the performance of EC, through EIS and other methods. The studied metal was a low-strength CS immersed in a 3.5% NaCl solution. The CS surface was obtained by polishing it (metal electrodes) with an abrasive paper of 120, 600 and 1200 mesh. Then, the electrodes were painted with an anti-corrosive EC, which contained Zn3 (PO4)2 as an anti-corrosion agent. The study of the influence of the CS surface Ra and its corrosion behaviour and of the evolution of the protective capacity systems on the EC performance was made by stationary (Ecorr and Tafel plot) and no-stationary Ec techniques (EIS and CA). In order to confirm the detachment and blistering on the coating, the coated CS samples were analyzed by a salt spray in a 7.69 % NaCl solution, with an IT of 15 days. The obtained results showed that the CS surface state directly influenced the coating performance and the Ec parameter values variation, as a function of IT in the NaCl solution. EIS was the most valid Ec method for the studied coatings.Item Enhancing the Supercapacitive and Conductivity Properties of Polypyrrole via In-situ Polymerization with HY Zeolite Nanoparticles(Springer link, 2020) Hamidouche, Fahim; Ghebache, Zohra; Boudieb, Naima; Sanad, Moustafa M. S.; Djelali, Nacer-EddineHighly stable zeolite HY/polypyrrole composite material was successfully fabricated by applying in-situ chemical polymerization approach. The functional properties of the prepared zeolite HY particles/polypyrrole were systematically inspected using XRD and FT-IR characterization techniques. Thermal stability and optical properties were consistently studied using TGA and UV–Vis spectroscopy techniques. The value of band gap energy (Eg) of the produced zeolite HY/polypyrrole nanocomposite was lower than the values of its individual components. Cyclic voltammetry studies concluded that HY/polypyrrole electrode material with mass ratio ~ 0.4 prepared at cold polymerization conditions ~ 0 °C exhibited the highest values of specific capacitance ~ 310 F g−1 and ionic conductivity ~ 1.7 S cm−1. The fabricated zeolite HY/polypyrrole composite material at 0 °C revealed a capacitance retention ~ 93.4%, while the other composite prepared at 25 °C possessed a capacitance retention ~ 72.4% after 500 charge/discharge cycles. The electrochemical impedance spectroscopy (EIS) measurement for the optimized composite electrode materials confirmed the cyclic stability after long term cycling of about 5000 cycles as a result of higher ionic conductivity between active material and ionic species than that value before cyclingItem Effect of Hematite on the Energy Storage Performance of Polyaniline/Zeolite HY/α-Fe2O3 Nanocomposite Supercapacitor Electrode(Springer, 2020) Ghebache, Zohra; Zitouni, Safidine; Hamidouche, Fahim; Boudieb, Naima; Benaboura, Ahmed; Trari, MohamedThe main goal of the present work is the elaboration of new nanocomposite conducting poly(aniline) with α-Fe2O3 nanoparticles in the presence of zeolite HY acid in aqueous electrolyte by chemical oxidative polymerization. Various formulations of the polymer were synthesized (5, 10, and 20% of α-Fe2O3) and the nanocomposites poly(aniline)/HY/α-Fe2O3 have been characterized by X-ray diffraction (XRD), SEM analysis, and FT-IR spectroscopy. The electrical conductivity and the UV–visible spectroscopy of the nanocomposites were also investigated. In addition, the electrochemical properties were studied by cyclic voltammetry. (CV) and electrochemical impedance spectroscopy. The optimal ratio between α-Fe2O3 and poly(aniline)/HY was found to be 5 wt%. The specific capacitances of poly(aniline)/HY and nanocomposite were found to be be 630, and 1000 F g−1 respectively at a scan rate of 5 mV/s. Besides, the material possesses a high energy density of 88.88 Wh kg−1 and a maximum power density of 1632.3 W kg−1. These electrochemical results indicate that the PANI/HY/α-Fe2O3 nanocomposites is an attractive candidate for the application in the high-performance energy storage systems.Item Synthesis and characterization of HY Zeolite-doped poly(aniline) by chemical oxidation method(2016) Ghebache, Zohra; Djelali, Nacer-Eddine; Zitouni, Safidine; Hamidouche, FahimItem Zeolite 4a coating by polypyrrole doped with chlorine(Materiale plastice, 2016) Hamidouche, Fahim; Djelali, Nacer-Eddine; Ghabache, ZohraAn organic–inorganic conductor’s Polypyrrole(Cl)/Zeolite 4A (PPy(Cl)/Z4A) was successfully synthesized by chemical oxidative polymerization at low and room temperature, using FeCl3 as initiator the reaction and dopant at the same time. After characterization, commodity we methods primarily on the polymerization of pyrrole with different molar ratios of [FeCl3]/[Pyrrole] in an aqueous medium, followed by a series of characterizations for the polymers obtained. The right ratio was used for the preparation of nanocomposites PPy(Cl)/Z4A. After each synthesis, the developed product is characterized by FTIR, SEM-EDX, XRD, electrical conductivity and cyclic voltammetry, in order to confirm the success of the process of synthesis and study their properties to specific applications envisagedItem Synthesis of nanocomposites based semiconductors of PPy(Cl)/Zeolite HY(Syscom 18 SRL, 2015) Hamidouche, Fahim; Djelali, Nacer-Eddine