La revue : Colloid and Polymer Science
Domaine : Materials
Mots Clés : Polyaniline 2-Chloroaniline Aluminum oxide Nanocomposite Electrochemical properties
Auteur : S. Benykhlef
Issn : 0303-402X Eissn : vol : 294, Num : , pp : 1877-1885
Date de publication : 2016-12-15
Résume : This paper presents the physicochemical, conductive, and electrochemical properties of different polyaniline (PANI)-derived polymer/Al2O3 nanocomposites synthesized by chemical oxidation polymerization method carried out in two stages: first, activation of the surface of the Al2O3 nanoparticles by hydrochloric acid and second, polymerization of 2-chloroaniline (2ClANI), aniline (ANI), and the copolymer (2ClANI-ANI) in the presence of Al2O3 by using ammonium persulfate as oxidant in aqueous hydrochloric acid. XRD and TEM results reveal the growth of the polymers on Al2O3 nanoparticles and the formation of PANI-derived polymer/Al2O3 nanocomposites. FTIR and UV-Vis show a systematic shifting of the characteristic bands of the polymers with the presence of Al2O3 nanoparticles. Moreover, these nanoparticles enhance the thermal stability of the polymers, as found by thermogravimetric analysis (TGA). Although the incorporation of Al2O3 nanoparticles reduces the electric conductivity of the polymers, the resulting nanocomposites still keep high conductivities, ranging between 0.3 × 10−2 and 9.2 × 10−2 S cm−1. As a result, the polymer/Al2O3 nanocomposites exhibit a good voltammetric response. All these synergetic features of the nanocomposites are assigned to the effective interaction of the polymers and Al2O3 particles at nanoscale.
La revue : Advances in Polymer Technology.
Domaine : Materials
Mots Clés : Hybrid materials Nanoparticle Zinc oxide 4-Chloroaniline Electrical conductivity
Auteur : F. Z. Dahou
Issn : 1548-0569 Eissn : vol : 35, Num : , pp : 411-418
Date de publication : 2016-10-05
Résume : Polymer/clay nanocomposite particles with 2‐aminophenol (2AP) and polyaniline and modified montmorillonite by copper minerals were synthesized using an in situ intercalative oxidative polymerization method. The nanocomposites were characterized by elementary analysis, X‐ray diffraction, FTIR, thermogravimetric analysis, transmission electron microscopy, and conductivity measurements. The insertion of the polymer into the layer of the clay was confirmed by X‐ray diffraction analysis, which shows a significantly larger d spacing expansion from 13.35 to 13.45 Å, thus indicating that the conducting polymer chain was aligned with layers of the clay. The conductivity of the nanocomposites salt is between 8.87×10−5 and 9.78×10−4 S/cm, probably due to the confined environment in the nanometer size layers of the nanocomposite. The electrochemical behavior of the polymers extracted from the nanocomposites has been studied by cyclic voltammetry. Good electrochemical response has been observed for polymers grown into M‐Cu; the redox processes indicate that the polymerization into M‐Cu is electroactive.
La revue : Journal of Inorganic and Organometallic Polymers and Materials
Domaine : Materials
Mots Clés : Hybrid materials Nanoparticle Zinc oxide 4-Chloroaniline Electrical conductivity
Auteur : A. Bekhoukh
Issn : 0022-2860 Eissn : vol : 27, Num : , pp : 13-20
Date de publication : 2017-01-15
Résume : 4-Chloroaniline (4ClAni) in the presence of zinc oxide (ZnO) nanoparticles were prepared by chemical oxidative polymerization in hydrochloric acid solution using Ammonium persulfate as oxidant. The effects of amount of ZnO nanoparticles (1, 1.5, 2, 2.5 and 3 g, respectively) on the properties of products were investigated. The obtained nanocomposites was characterized using XRD, IR, UV–visible, and XPS which confirmed the incorporation of the nanoparticle ZnO in the P(4ClAni) matrix and the maximum interaction occurs for 2 g ZnO loading. The TGA analysis was used to confirm the thermal stability and number of water molecules in each nanocomposites chain unit. Although the incorporation of ZnO nanoparticles reduces the electric conductivity of the P(4ClAni), the resulting nanocomposites still keep high conductivities, ranging between 2.19 × 10−2 and 5.92 × 10−4 S cm−1. Good electrochemical response has been observed for samples of amounts ZnO less than 2 g; the observed redox processes indicate that the polymerization on ZnO nanoparticles produces electroactive polymers. The P(4ClAni) layer adhered well to the ZnO nanoparticles and can be used as practical applications.
La revue : Journal of Molecular Structure
Domaine : Materials
Mots Clés : alcohol dehydrogenation; biomass; lignin; bio-char; CO2 gasification; activated carbon; sodium
Auteur : S.Benyakhou
Issn : 2073-4344 Eissn : vol : 1150, Num : , pp : 580-585
Date de publication : 2017-09-27
Résume : Hydrochloric acid functionalized silica gel (SiO2) has been successfully used for the grafting of poly(2-Aminophenyl disulfide) (poly(2APhS)) moieties through in-situ polymerization in the presence of ammonium peroxodisulfate (APS) as oxidant. The organic-inorganic hybrid (poly(2APhS)/SiO2 with different amounts of SiO2: 0.5 g, 1.5 g and 2 g) were thoroughly characterized through powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and ultraviolet spectroscopy (UV) measurements. The results confirm the successful formation of the poly(2APhS)/SiO2 composite. The surface morphology of the samples was characterized by transmission electron microscopy (TEM). The obtained images show the formation of poly(2APhS) on surface of silica gel. Although the incorporation of SiO2 nanoparticles reduces the electric conductivity of the poly(2APhS), the resulting samples still keep high conductivities, ranging between 8.2 × 10−4 to 1.1 × 10−6 S cm−1. The electrochemical properties of the composite were characterized by the cyclic voltammetry. The comparison between the different samples shows that the electrochemical activity is significantly depending on the amount of added SiO2. There is a clear and good electroactivity for poly(2APhS)/SiO2 with amounts of SiO2: 0.5 g and 1.5 g, respectively, compared to that observed in materials nanocomposite with amounts of SiO2: 2.0 g. However, that effect may be explained by a decrease of polymer in surface area with increase amount of SiO2 nanoparticle.
La revue : Catalysts.
Domaine : Materials
Mots Clés : alcohol dehydrogenation; biomass; lignin; bio-char; CO2 gasification; activated carbon; sodium
Auteur : F. J. G. Mateos
Issn : 2073-4344 Eissn : vol : 7, Num : , pp : 308
Date de publication : 2017-09-27
Résume : The properties of lignin and its potential as a renewable source make it an ideal precursor for carbon products. Specifically, the high content of Na observed in Kraft lignin makes this industrial by-product an interesting precursor for the preparation of catalysts for different applications. In this work, basic activated carbons with different textural properties and surface chemistry were obtained from Kraft lignin by direct carbonization at various temperatures. The influence of a further washing treatment and partial gasification with CO2 was also evaluated. The carbon catalysts were tested as catalysts for the alcohol decomposition reaction. In this sense, 2-propanol, a molecule widely used for testing the acidic-basic character of heterogeneous catalysts, was selectively transformed into acetone, meanwhile, ethanol and methanol yielded mainly acetaldehyde and formaldehyde, respectively.
La revue : Journal of Physics and Chemistry of Solids.
Domaine : Materials
Mots Clés : Nanocomposites. Aniline. Zinc oxide. Zinc chloride. Electrochemical properties
Auteur : S.Daikh
Issn : 1068-3755 Eissn : vol : 121, Num : , pp : 78-84
Date de publication : 2018-10-15
Résume : An in-situ polymerization method has been employed to prepare HCl-doped polyaniline (PANI)/ZnO nanocomposites and (HClZnCl2) doped PANI/ZnO. Structural characteristics were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV), thermogravimetric analysis (TGA) and Transmission Electron Micrographs (TEM). TGA results showed that the decomposition of the HCl doped PANI/ZnO nanocomposites was less than that of (HClZnCl2) doped PANI/ZnO nanocompositess. Conduction studies were done by using four-probe method. Electrical conductivity study shows an increase in the conductivity of the samples with the (HClZnCl2) doped) PANI/ZnO to 0.081 S cm−1. To further explore the advantages of these nanocomposites for real applications, we investigated the electrochemical properties of these samples electrodes, the (HClZnCl2-doped) PANI/ZnO nanocomposite presented much higher electrochemical response to (HCl-doped) PANI/ZnO and (ZnCl2-doped) PANI/ZnO nanocomposites.
La revue : Surface Engineering and Applied Electrochemistry.
Domaine : Materials
Mots Clés : Adsorption. Isotherms. Quinmerac Diatomite activation
Auteur : K. Khaldi
Issn : 1068-3755 Eissn : vol : 54, Num : , pp : 194-202.
Date de publication : 2018-11-15
Résume : Algerian aluminosilicate mineral natural diatomite and its modified variant were applied to remove quinmerac (QM)—a week acid herbicide from aqueous solutions. Then samples were investigated by the transmission electron microscopy, X-ray diffraction analysis, X-ray fluorescence and physical adsorption of gases. The adsorption experiments were carried out at ambient temperature in baths at different pH and the results showed that the amount of adsorbed QM increased at a higher pH, reaching a maximum at pH 2.5. The Langmuir model provided the best correlation of the experimental data for adsorption equilibrium. It was found that the modified diatomite exhibits a slightly better efficiency in the removal of QM than natural diatomite; this is why it could be considered to be an alternative material for removing a specific pollutant from environment.
La revue : Polymer Science, Series B.
Domaine : Materials
Mots Clés : Conjugated polymer. Poly(orthophenylenediamine). Modifed-clay. Electrochemical properties
Auteur : A. Belalia
Issn : 1560-0904 Eissn : vol : 60, Num : , pp : 816-824
Date de publication : 2018-11-15
Résume : PANI and PANI-SiO2 were prepared by chemical oxidative polymerization in acidic medium of hydrochloric acid (1 M) using ammonium persulfate as oxidant. The developed adsorbents were characterized using various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and physical adsorption of gases. To further explore the advantages of these materials for real applications, we investigated the electrochemical properties of these samples electrodes. The efficiency of PANI, SiO2 and PANI-SiO2 for the adsorptive removal of phenol (Ph) from aqueous solutions has been evaluated with respect of several experimental conditions. These latter has to do with the effect of contact time and the effect of pH. The experimental data were analyzed by the Langmuir and Freundlich isotherm models. The Langmuir isotherm fits the experimental data very well due to the homogeneous distribution of active sites onto adsorbents surface. The kinetics study revealed that adsorption of Ph onto three samples follows the pseudo-second order kinetic model.
La revue : Journal of Molecular Structure
Domaine : Materials
Mots Clés : Conjugated polymer. Poly(orthophenylenediamine). Modifed-clay. Electrochemical properties
Auteur : I.Khelifa
Issn : 0022-2860 Eissn : vol : 1178, Num : , pp : 327-332
Date de publication : 2019-02-15
Résume : This work describes the synthesis and characterization of new poly(o-phenylenediamine (PoPD)/modified-clay nanocomposite materials. For the synthesis, the raw clay (named as Mag) used in this study was from Maghnia (west Algeria), (Mag) clay was ion-exchanged with cobalt(II) sulfate hydrate and copper sulfate. The modified-clays were then dispersed in a oPD monomer-containing acidic solution to carry out in-situ intercalative oxidative polymerization by ammonium persulfate. XRF and XRD characterization reveal the success of ion-exchange to form highly intercalated Mag-Co and Mag-Cu clays. After polymerization, the disappearance of the interlayer-spacing diffraction peak for the PoPD-Mag-Cu and PoPD-Mag-Co nanocomposites points out fully exfoliation of the clay structure. The formation of intercalated PoPD into modified-clay nanocomposites was confirmed by XRD, TEM, TG analysis, FTIR spectroscopy and UV–vis studies. The nanocomposites show optical properties and the redox processes observed by cyclic voltammetry indicate that the reported polymerization into modified-clays leads to electroactive hybrid materials. All these properties make these polymer/clay nanocomposites attractive materials for multiple applications.
La revue : Journal of Thermal Analysis and Calorimetry.
Domaine : Materials
Mots Clés : Pyrrole N-Methylpyrrole Zirconium(IV) oxide Nanocomposites Electrochemical properties
Auteur : K. Yamani
Issn : 1388-6150 Eissn : vol : 135, Num : , pp : 2089-2100
Date de publication : 2019-05-17
Résume : New polypyrrole (PPy)-derived polymer/ZrO2 nanocomposite materials are prepared by single-step oxidative polymerization of pyrrole (Py) and/or N-methylpyrrole (mPy) in the presence of HCl-functionalized ZrO2 nanoparticles and ammonium persulfate. The physicochemical features of the PPy–ZrO2, poly(Py-co-mPy)–ZrO2 and PmPy–ZrO2 hybrids were analyzed by XPS, FTIR, XRD and UV–Vis techniques. To explore the advantages of these nanocomposites for potential applications, their thermal, conductive and electrochemical properties were investigated. The characterization reveals that a chemical bonding, based on electrostatic interactions, is established between the polymers and the ZrO2 nanoparticles. Interestingly, it is found that the growth of polymer on the surface of Cl-functionalized ZrO2 becomes more significant as the Py moiety (–NH– species) content in the polymer increases. The thermal stability and conductivity of the polymers increase by hybridization with the ZrO2 nanoparticles. This is assigned to the affective interaction of the polymers with the ZrO2 nanoparticles. Particularly, the resulting nanocomposites keep high conductivities, ranging between 0.323 and 0.929 S cm−1. Finally, voltammetric characterization shows that the PPy–ZrO2 and poly(Py-co-mPy)–ZrO2 nanocomposites are electroactive, thus demonstrating their capability for electrochemical applications. These results highlight the great influence of the nanoparticle interface and the nature of monomer on the nanocomposite formation and properties.
La revue : Journal of Inorganic and Organometallic Polymers and Materials.
Domaine : materials
Mots Clés : Nanocomposites. Polymer-SiC. Optical properties. Electrochemical properties
Auteur : H. Soltani
Issn : 1574-1443 Eissn : vol : 29, Num : , pp : 841-850
Date de publication : 2019-01-02
Résume : In this study, polyaniline/Clay nanomaterials (PANI/Clay) was synthesized through one-step method and used as an adsorbent to remove Cu(II) ions from aqueous solution. The PANI/Clay was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, cyclic voltammograms and physical adsorption of gases. Adsorption parameters such as contact time, pH value, and initial metal ion concentration were investigated. The results revealed that PANI/Clay exhibits a much higher adsorption capacity than the natural clay; the attractive adsorption capacity reached 22.77 mg/g with 0.05 g of 100 mg PANI/Clay at an initial pH solution of 6 and adsorption temperature of 25 °C. Moreover, the Langmuir model well describes the adsorption data with the maximum sorption capacity of 22.77 mg/g. Pseudo-second-order model can fit well the kinetic data obtained from batch Cu(II) removal experiments. The Cu(II) adsorption on PANI/Clay nanocomposite was mainly attributed to electrostatic interaction, donor–acceptor interaction and intermolecular interactions.
La revue : Journal of Molecular Structure.
Domaine : materials
Mots Clés : Nanocomposites. Polymer-SiC. Optical properties. Electrochemical properties
Auteur : F.Z.Kouidri
Issn : 0022-2860 Eissn : vol : 1188, Num : , pp : 121-128
Date de publication : 2019-07-15
Résume : Hybridization of nanomaterials constitutes an interesting approach to boost and develop novel properties and applications. In this work, different polyaniline (PANI)-derived polymer-SiC nanocomposites have been successfully synthesized by facile surface-initiated polymerization of aniline (ANI) and/or 4-Anisidine (4ANS) on HCl-functionalized SiC. The obtained materials were characterized by different analytical techniques as well as solubility, conductivity and electrochemical tests. The effect of the nature and combination of the substituents in the polymer was analyzed. XRD; thermogravimetry; and vibrational FTIR spectroscopy revealed effective polymerization and interaction between the polymers and the SiC nanoparticles to form PANI-SiC, poly(ANI-co-4ANS)-SiC and P4ANS-SiC nanocomposites. The presence of electron-donating (para) -OCH3 substituents was found to hinder this interaction and/or to retard the polymerization, decreasing the content and crystallinity of the polymer in the nanocomposite. However, the dispersibility of the nanocomposites in different solvents greatly increased, and the electroactive and optical properties were affected. As a result, the poly(ANI-co-4ANS)-SiC nanocomposite exhibits higher dispersibility, lower band gap, similar conductivity and richer electroactivity than PANI-SiC, and an intermediate polymerization yield. Then, engineering the substituents of polymer chains is demonstrated to be an efficient approach to tailor the properties of (PANI)-derived polymer-SiC nanocomposites.
La revue : Chemical Physics Letters
Domaine : materials
Mots Clés : Hybrid materialsPolyanilineZnOOptical propertiesElectrochemical properties
Auteur : S. Bousalem
Issn : 0009-2614 Eissn : vol : , Num : , pp :
Date de publication : 2020-01-08
Résume : Hybrid-materials were prepared via chemical polymerization in presence of aniline with various amounts of ZnO. The structural, functional, optical, morphological and electrical properties of nanocomposites were investigated by XRD, FT-IR, UV-Visible, TGA, SEM and electrical conductivity. XRD and SEM analysis shows the formation of nanocomposite and confirms the amorphous and crystalline nature of material. FT-IR spectrum reveals the functional groups present in the samples and the electroactive and optical properties were affected. Results showed that our nanocomposites exhibited a direct optical energy gap that decreased from 3.12 to 2.76 eV with the increment of the amounts of ZnO in nanocomposite.
