Material Research School

Eşfahān, Iran

Material Research School

Eşfahān, Iran
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Nasrollahzadeh M.,University of Qom | Sajadi S.M.,Kurdistan Regional Government | Rostami-Vartooni A.,University of Qom | Bagherzadeh M.,Material Research School
Journal of Colloid and Interface Science | Year: 2015

We report the green synthesis of palladium/CuO nanoparticles (Pd/CuO NPs) using Theobroma cacao L. seeds extract and their catalytic activity for the reduction of 4-nitrophenol and Heck coupling reaction under aerobic conditions. The catalyst was characterized using the powder XRD, TEM, EDS, UV-vis and FT-IR. This method has the advantages of high yields, elimination of surfactant, ligand and homogeneous catalysts, simple methodology and easy work up. The catalyst can be recovered from the reaction mixture and reused several times without any significant loss of catalytic activity. © 2015 Elsevier Inc.

Nasrollahzadeh M.,University of Qom | Sajadi S.M.,Soran University | Rostami-Vartooni A.,University of Qom | Bagherzadeh M.,Material Research School | Safari R.,University of Qom
Journal of Molecular Catalysis A: Chemical | Year: 2015

We report the facile synthesis of environmentally benign Cu NPs/perlite composites without employing any toxic reductants or capping agents. Renewable natural Euphorbia esula L. not only functioned as a reductant, but also served as a stabilizer for the formation of Cu NPs. Cu NPs synthesized using aqueous extract of the leaves of E. esula L. was immobilized on perlite by a very simple and inexpensive method. The structural investigation was performed using XRF, XRD, SEM, EDS, TEM, TG-DTA, BET and FT-IR. The Cu NPs/perlite shows favorable activity and separability on the catalytic reduction of 4-nitrophenol, and can be reused several times without a decrease in the catalytic activity. Their reaction rate constant was calculated according to the pseudo-first-order reaction equation. © 2015 Elsevier B.V.

Mortazavi S.Z.,Amirkabir University of Technology | Parvin P.,Amirkabir University of Technology | Reyhani A.,Amirkabir University of Technology | Golikand A.N.,Material Research School | Mirershadi S.,Material Research School
Journal of Physical Chemistry C | Year: 2011

In this work, Pd nanoparticles were synthesized by pulsed nanosecond laser ablation in deionized water using Q-switched Nd:YAG and ArF excimer lasers, independently. The aim is to investigate the wavelength dependence of nanoparticle formation mechanisms using IR and UV laser irradiations. Pd nanoparticles fabricated by a Q-switched Nd:YAG laser show a perfect spherical morphology, whereas those due to the ArF excimer laser undergo fragmental shapes. Furthermore, the production rate of Pd nanoparticles generated at IR is noticeably greater than that at UV wavelength. Moreover, the plasma temperature induced by the Nd:YAG laser is higher than that generated by the ArF laser mainly due to the stronger inverse Bremsstrahlung process at the IR region. It was shown that the ArF laser fabricates palladium oxide structure with much higher rate with respect to the Nd:YAG laser. © 2011 American Chemical Society.

Bagherzadeh M.,Material Research School | Pirmoradian M.,Islamic Azad University at Shahreza | Riahi F.,Material Research School
Electrochimica Acta | Year: 2014

Here, electrochemical determination of lead (Pb2+) and copper (Cu2+) ions, by using diethylenetriamine pentaacetic acid (DTPA) functionalized dopaminated Fe3O4 (Fe3O 4/DA) magnetic nanoparticles, MNPs, (Fe3O 4/DA/DTPA), is reported. First, step by step construction of Fe 3O4/DA/DTPA was characterized and confirmed by spectroscopic methods. Then, a simple and new modified magnetic electrode was prepared by employing permanent magnet into a carbon paste electrode (MCPE) and collecting functionalized MNPs in each steps. The prepared modified electrodes, electrochemically characterized and further proofs was obtained in the presence of Fe(CN)6]3-/4- as a redox probe. Sensing ability of the modified electrodes toward two valet cations was evaluated by following striping voltammetry responses of pre-concentrated ions on top of them. The MCPE/Fe 3O4/DA/DTPA electrode showed selective response to Pb 2+ and Cu2+ ions. Consequently, the electrode response to Pb2+ and Cu2+ was evaluated as a function of solution pH, pre-concentration time, and ions concentrations. Finally, in optimized conditions, two linear ranges from 1.0 × 10-9 to 5.0 × 10-6 and 1.0 × 10-5 to 1.0 × 10-3 M Pb2+ with a detection limit (D.L.) of 7.8 × 10-10 M Pb2+, and a linear range from 5.0 × 10-9 to 1.0 × 10-3 M Cu2+ with a D.L. of 9.5 × 10 -10 M Cu2+ were observed for separate determination of Pb2+ and Cu2+, respectively. Also, two linear ranges from 1.0 × 10-9 to 5.0 × 10-8 and 5.0 × 10-7 to 1.0 × 10-3 M Pb2+ with a D.L. of 8.2 × 10-9 M Pb2+, and a linear range from 5.0 × 10-9 to 1.0 × 10-4 M Cu2+ with a D.L. of 2.1 × 10-9 M Cu2+ were observed for simultaneous determination of Pb2+ and Cu2+. The obtained results will be presented and described here. © 2013 Elsevier Ltd. All rights reserved.

Bagherzadeh M.,Material Research School | Heydari M.,Islamic Azad University at Shahreza
Analyst | Year: 2013

Herein, graphene nanosheets (GNS) were synthesized, by a green and facile method based on reduction by glucose, and characterized. Afterwards, a carbon paste electrode (CPE) was modified with GNS by casting and drying GNS on top of the CPE (CPE/GNS). The behavior of the CPE/GNS towards dopamine (DA) and ascorbic acid (AA) was investigated by electrochemical methods and the obtained results showed that the CPE/GNS had adsorbed only DA. Based on this behavior, the DA molecules were pre-concentrated on top of the CPE/GNS, followed by stripping in DA free solution. Subsequent to experimental and instrumental optimization, a calibration curve from 2.0 × 10-6 to 1.0 × 10-3 M DA, r2 = 0.99 (±0.01), with detection limit (DL) = 8.5 × 10-7 M DA, sensitivity = 15.4 (±0.94) μA, and RSD = 6.1 was observed in the presence of 1.0 × 10-3 M AA. Finally, the performance of the CPE/GNS was successfully tested in a pharmaceutical sample. This work provides a promising strategy for DA detection in the presence of biological interferences, e.g. AA, with high sensitivity and simple characteristics. © 2013 The Royal Society of Chemistry.

Aghazadeh M.,Tarbiat Modares University | Aghazadeh M.,Material Research School | Golikand A.N.,Material Research School | Ghaemi M.,Golestan University
International Journal of Hydrogen Energy | Year: 2011

Nickel hydroxide was deposited via cathodic electrodeposition from low-temperature 0.005 M NiCl2 bath without using any surfactant or template. The cathodic current density was 1 mA cm-2 and stainless steel was used as the cathode. The XRD pattern confirmed that the prepared sample has a pure brucite crystal phase of β-Ni(OH)2 and the broadening of diffraction peaks showed that the particles size of the prepared β-Ni(OH)2 is extremely small. Thermal behavior and composition of the prepared β-Ni(OH)2 were investigated by DSC-TG and FT-IR analyses. Morphological characterization by SEM and TEM revealed that β-Ni(OH)2 is composed of well dispersed ultrafine particles with size of about 5 nm. The electrochemical properties of the prepared nanoparticles were studied by means of cyclic voltammetry (CV) and galvanostatic charge-discharge tests in 1 M KOH. The prepared β-Ni(OH)2 nanoparticles showed excellent capacitance behavior of 740 F g-1 in the potential window of 0-0.55 V vs. Ag/AgCl. These results make the β-Ni(OH)2 nanoparticles as a promising candidate for the supercapacitor electrodes. © 2011 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Adelkhani H.,Material Research School | Ghaemi M.,Golestan University
Journal of Alloys and Compounds | Year: 2010

This paper describes the electrochemical capacitor behavior of manganese dioxide (MD, MnO2) samples that were prepared by direct current (DCMD) and pulse current (PCMD) electrodeposition. The capacitive characteristics of the samples were studied in 0.5 M aqueous Na2SO4 solution using the cyclic voltammetry (CV) method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), chemical composition analyses and the Barrett-Joyner-Halenda (BJH) method were employed to characterize the samples. In the study of the effect of scan rate on capacitance, it was revealed that PCMD displayed higher capacities than DCMD for all scan rates. The higher capacitive performance of PCMD was attributed to its porosity (specific surface area, pore volume, and pore-size distribution), chemical composition and structural properties. © 2009 Elsevier B.V. All rights reserved.

The effects of acidity of electrolyte (pH) on the hysteresis behavior, the specific surface area, and nanostructure morphology of electrolytic manganese dioxides (EMDs) have been studied by using the Barrett-Joyner-Halenda (BJH) analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM) images analysis. EMD samples are electrodeposited at a variable pH (6 to 1) and many fixed pH (2, 3, 4, 5, and 6). Results indicate that pH play key roles in the characteristics of EMD. The samples obtained at low pH (2 and 3) show multi-branched morphology and represent a H4 hysteresis loop. At pH 4 and 5, a uniform and dense structure of MnO 2 is obtained without hysteresis behavior. The sample electrodeposited at pH 6 shows a regular reticulate, that its adsorption-desorption isotherm show hysteresis behavior. By electrodeposition at a variable pH, the sample shows a cauliflower-like and multi-branched form. From the viewpoint of classification of isotherm, pH strongly affects on Type of isotherm. The results show that γ-MnO 2 is as main-product of electrodeposition and α-MnO 2 and β-MnO 2 were obtained as side-product at low and high pH, respectively. © 2012 Elsevier B.V.

Nassiri-Mofakham N.,Material Research School
Physica A: Statistical Mechanics and its Applications | Year: 2015

This paper concerns the magneto-fluid dynamics modeled by the stochastic flow where the turbulent term is driven by the random forcing. Magnetohydrodynamic (MHD) turbulence can be interpreted in terms of a standard map (SM), modeling perturbed Hamiltonian systems, to explain some of the features of the problem. The dynamics generated by SM, although being chaotic, are influenced by periodic islands embedded in the chaotic sea due to stickiness effect and also to the behavior of the diffusion coefficient. Anomalous diffusion exists only up to some crossover time, beyond which the diffusion is Gaussian consistent with quasi-linear predictions. The results can be applicable to systems where there exist intensive interaction between a stochastic turbulent system and waves. © 2014 Elsevier B.V. All rights reserved.

Aghazadeh M.,Material Research School | Yousefi T.,Material Research School
Materials Letters | Year: 2012

Gd 2O 3 nanorods were prepared by a template free two-step process: first, Gd(OH) 3 was galvanostatically deposited from low-temperature nitrate bath on the steel substrate by electrogeneration of base. Then heat treated at 700°C for 3 h. The morphology and crystal structure of the obtained oxide powder were analyzed by means of scanning and transmission microscopy (SEM and TEM), X-ray diffraction (XRD) and FT-IR spectroscopy. The analyses revealed that the product has cubic crystalline structure and rod morphology with approximately diameter of 20-100 nm and the length of up to 2 μm. The results showed that low-temperature cathodic electrodeposition followed by heat treatment can be recognized as an easy and facile method for the preparation of Gd 2O 3 nanorods. © 2011 Elsevier B.V. All rights reserved.

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