Loading...
Search for: sulfide
0.007 seconds
Total 262 records

    A novel iron complex containing an N,O-type bidentate oxazoline ligand: Synthesis, X-ray studies, DFT calculations and catalytic activity

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Vol. 133, issue , Jun , 2014 , p. 432-438 Amini, M ; Arab, A ; Derakhshandeh, P. G ; Bagherzadeh, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    Abstract
    A five-coordinated Fe(III) complex with the distorted trigonal bipyramidal configuration was synthesized by reactions of FeCl36H2O and 2-(2′-hydroxyphenyl)oxazoline (Hphox) as a bidentate ON donor oxazoline ligand. Complex [Fe(phox)2Cl] was fully characterized, including by single-crystal X-ray structure analysis. DFT calculations were accompanied with experimental results in order to obtain a deeper insight into the electronic structure and vibrational normal modes of complex. Oxidation of sulfides to sulfoxides in one-step was conducted by this complex as catalyst using urea hydrogen peroxide (UHP) in mixture of CH2Cl 2/CH3OH (1:1) under air at room temperature. The results show that using... 

    Simultaneous separation of H2S and CO2 from CH4 by a high silica CHA-type zeolite membrane

    , Article Journal of Membrane Science ; Vol. 470, issue , 2014 , pp. 159-165 ; ISSN: 03767388 Maghsoudi, H ; Soltanieh, M ; Sharif University of Technology
    Abstract
    A high silica CHA-type membrane was synthesized by the in-situ crystallization method on a disk like α-alumina porous support to separate both acid (H2S, CO2) gases from methane. The membrane showed a permeance of 3.39×10-8mol/m2sPa for pure CO2with CO2/CH4 ideal selectivity of 21.6 at 303K and 100kPa pressure difference across the membrane. The membrane was also tested with N2 and O2 pure gases indicating a small O2/N2 selectivity of 1.2-1.4, which shows that this type of membrane is not suitable for O2/N2 separation. The membrane performance was also analyzed by binary (CO2-CH4) and ternary (H2S-CO2-CH4) gas mixtures, with compositions near the real sour natural gas (CO2: 2.13mol%, H2S:... 

    Synthesis, X-ray studies, and catalytic activity of tridentate Schiff base dioxo-molybdenum(VI)

    , Article Journal of Coordination Chemistry ; Volume 67, Issue 14 , 2014 ; ISSN: 00958972 Amini, M ; Khaksar, M ; Boghaei, D. M ; Bagherzadeh, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    Abstract
    The reaction of a solution of MoO2(acac)2 in CH3OH and salicylidene 2-picoloyl hydrazone as a tridentate ONO donor Schiff base (ONO) afford a six-coordinated Mo(VI) complex [MoO2(ONO)(CH3OH)], with a distorted octahedral configuration. [MoO2(ONO)(CH3OH)] was isolated as an air-stable crystalline solid and fully characterized by single-crystal X-ray structure analysis. [MoO2(ONO)(CH3OH)] shows reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the oxidant at room temperature under air  

    Graphene/PbS as a novel counter electrode for quantum dot sensitized solar cells

    , Article ACS Photonics ; Vol. 1, issue. 4 , March , 2014 , pp. 323-330 ; ISSN: 23304022 Parand, P ; Samadpour, M ; Esfandiar, A ; Iraji Zad, A ; Sharif University of Technology
    Abstract
    PbS nanoparticles were in situ deposited on graphene sheets by a successive ionic liquid adsorption and reaction method to prepare a graphene/PbS composite counter electrode for CdS/CdSe quantum dot sensitized solar cells (QDSCs). Under 1 sun illumination, the cells with graphene/PbS counter electrodes (CEs) show a maximum energy conversion efficiency of 2.63%, which is remarkably higher than that of those employing PbS (1.28%) or graphene (0.23%) CEs. Electrochemical impedance spectroscopy analysis shows that graphene/PbS composite counter electrodes have lower charge-transfer resistance at the interface of the CE and the polysulfide redox electrolyte, compared to those cells with PbS and... 

    Super-hydrophilic characteristic of thermochemically prepared CdS nanocrystals

    , Article Physica E: Low-Dimensional Systems and Nanostructures ; Vol. 58 , April , 2014 , pp. 146-152 ; ISSN: 13869477 Marandi, M ; Taghavinia, N ; Babaei, A ; Sharif University of Technology
    Abstract
    CdS nanocrystals were thermochemically (thermally activated) synthesized thorough the reaction between CdSO4 and Na2S 2O3 in an aqueous solution. Thioglycolic Acid (TGA) was used as the capping agent and catalyst of the reaction. The method was based on heat activated dissociation of Na2S2O3 and controllable release of S and free electrons in the solution. CdS NCs were formed by heating the sample solution at 96 C for 1 h. The results of optical spectroscopy and transmission electron microscopy demonstrated round shape NCs with sizes about 3.0 nm. The nanocrystals were also luminescent and represented a broad emission with a peak located at 515 nm and FWHM of 160 nm. Several samples were... 

    Vertically aligned ZnO@CdS nanorod heterostructures for visible light photoinactivation of bacteria

    , Article Journal of Alloys and Compounds ; Vol. 590 , 2014 , pp. 507-513 ; ISSN: 09258388 Zirak, M ; Akhavan, O ; Moradlou, O ; Nien, Y. T ; Moshfegh, A. Z ; Sharif University of Technology
    Abstract
    Vertically aligned ZnO@CdS nanorod heterostructure films with various loadings of CdS nanoparticle shell were synthesized and applied in photoinactivation of Escherichia coli bacteria under visible light irradiation. While neither the bare ZnO nanorods (with band-gap energy (Eg) of ∼3.28 eV) under visible light irradiation nor the nanorod heterostructures in dark exhibited any significant antibacterial activity, the ZnO@CdS nanorod heterostructures (with Eg ∼2.5-2.6 eV) could successfully inactivate the bacteria under visible light irradiation. Furthermore, it was found that an optimum loading of the CdS shell (corresponding to the effective thickness less than ∼15 nm) is required to achieve... 

    Leaching kinetics of stibnite in sodium hydroxide solution

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 27, Issue 2 , February , 2014 , Pages 325-332 ; SSN: 10252495 Dodangeh, A ; Halali, M ; Hakim, M ; Bakhshandeh, M. R ; Sharif University of Technology
    Abstract
    The leaching kinetics of stibnite in basic solution has been investigated. Spherical pellets of antimony sulphide were dissolved in 1 molar sodium hydroxide solutions at different temperatures. It was found that the shrinking core with ash layer model could satisfactorily explain the dissolution process. Using this model, it was found that initially the rate controlling step was a chemical reaction with activation energy of 10.2 kJ/mol. As the ash layer built up, diffusion through the ash layer became the rate controlling step. The activation energy for this step was found to be 33.4 kJ/mol. It was also observed that smaller particle size, larger solid to liquid ratio, and higher NaOH... 

    Solvothermal synthesis of CuMS2 (M=A1, In, Fe) nanoparticles and effect of coordinating solvent on the crystalline structure

    , Article Scientia Iranica ; Volume 21, Issue 6 , 2014 , Pages 2468-2478 ; ISSN: 10263098 Vahidshad, Y ; Ghasemzadeh, R ; Zad, A. I ; Mirkazemi, S. M ; Masoud, A ; Sharif University of Technology
    Abstract
    CuMS2 (M=A1, In, Fe) ternary compounds were synthesized via the facile polyol method in autoclave. Depending on the functional groups of solvent and surfactant, the structure of the nanocrystals can be controlled in the form of wurtzite or chalcopyrite. The chalcopyrite structure was obtained when the precursors solved in the mixture of diethylene glycol, polyethylene glycol 600 and ammonium hydroxide. When the solvent was replaced by ethylene diamine, the wurtzite was obtained along with chalcopyrite (polytypism). The products were characterized by X-Ray Diffraction (XRD) for analysis of structural properties, Transmission Electron Microscopy (TEM) for studying morphological... 

    CdS nanoparticle sensitized titanium dioxide decorated graphene for enhancing visible light induced photoanode

    , Article Applied Surface Science ; Vol. 320, issue , 30 November , 2014 , pp. 772-779 ; ISSN: 01694332 Yousefzadeh, S ; Faraji, M ; Nien, Y. T ; Moshfegh, A. Z ; Sharif University of Technology
    Abstract
    CdS/TiO2/graphene (CTG) nanocomposite thin films were synthesized by a facile production route. The TiO2/graphene (TG) nanocomposite was initially fabricated by sol-gel method in such a way that TiO2 nanoparticles loaded on graphene oxide (GO) sheet via photocatalytic process. Then, CdS nanoparticles were deposited on the TG thin film by successive ion layer adsorption and reaction process (SILAR) approach. Based on atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, the TG thin film possessed a larger surface area as compared with the pure TiO2 thin film due to presence of graphene sheet. UV/visible spectroscopy exhibited... 

    A water-oxidizing dinuclear iron complex as an efficient catalyst toward organic sulfide oxidation

    , Article Journal of Coordination Chemistry ; Vol. 67, issue. 18 , Jul , 2014 , p. 3026-3032 Amini, M ; Najafpour, M. M ; Zare, M ; Holynska, M ; Moghaddam, A. N ; Bagherzadeh, M ; Sharif University of Technology
    Abstract
    In this paper, we report that a known dinuclear Fe complex, [tpa(H2O)FeOFe(H2O)tpa](ClO4)4 (tpa: tris(2-pyridylmethyl)amine), is an efficient catalyst toward organic sulfide oxidation in the presence of urea-hydrogen peroxide  

    Monolithic quantum dot sensitized solar cells

    , Article Journal of Physics D: Applied Physics ; Volume 46, Issue 48 , December , 2013 ; 00223727 (ISSN) Samadpour, M ; Ghane, Z ; Ghazyani, N ; Tajabadi, F ; Taghavinia, N ; Sharif University of Technology
    2013
    Abstract
    We report a new design of solar cells based on semiconductor quantum dots (QDs), monolithic quantum dot sensitized solar cells (MQDSCs). MQDSCs offer the prospect of having lower cost and a simpler manufacturing process in comparison to conventional double substrate QDSCs. Our proposed monolithic QDSCs have a triple-layer structure, composed of a CdS sensitized mesoporous TiO2 photoanode, a scattering layer made by a core-shell structure of TiO 2/SiO2, and a carbon active/graphite counter electrode layer, which are all deposited on a single fluorine doped tin oxide (FTO) glass substrate. Mesoporous TiO2 was sensitized with CdS QDs by successive ionic layer adsorption and reaction. Here,... 

    Dependence of photovoltaic performance of solvothermally prepared CdS/CdTe solar cells on morphology and thickness of window and absorber layers

    , Article Journal of Materials Science: Materials in Electronics ; Volume 24, Issue 9 , 2013 , Pages 3564-3574 ; 09574522 (ISSN) Akhlaghi, M. H ; Mohammadi, M. R ; Sharif University of Technology
    2013
    Abstract
    In the present work a new strategy for straightforward fabrication of CdS/CdTe solar cells, containing CdS nanowires and nanoparticles as a window layer and CdTe nanoparticles and microparticles as an absorber layer, are reported. CdS and CdTe nanostructures were synthesized by solvothermal method. X-ray diffraction analysis revealed that highly pure and crystallized CdS nanowires and nanoparticles with hexagonal structure and CdTe nanoparticles with cubic structure were obtained. Atomic force microscope and field emission scanning electron microscope images showed that CdS nanowires with length of several μm and average diameter of 35 nm, CdS nanoparticles with average particle size of 32... 

    Synergism of oxygen vacancy and carbonaceous species on enhanced photocatalytic activity of electrospun ZnO-carbon nanofibers: Charge carrier scavengers mechanism

    , Article Applied Catalysis A: General ; Volume 466 , September , 2013 , Pages 153-160 ; 0926860X (ISSN) Samadi, M ; Shivaee, H. A ; Pourjavadi, A ; Moshfegh, A. Z ; Sharif University of Technology
    2013
    Abstract
    Novel ZnO-carbon and ZnO nanofibers were fabricated by electrospinning of polymer precursor followed by subsequent annealing in nitrogen and air, respectively. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) indicated the smooth and beadless nanofibers with wurtzite crystal structure. X-ray photoelectron spectroscopy (XPS) showed the presence of oxygen vacancies (VO) and chemisorbed O2 on the surface of the samples. Band gap narrowing of the ZnO-carbon nanofibers in comparison to ZnO were measured by diffuse reflectance spectroscopy (DRS). Photo-degradation of azo dye under the UV and visible light was evaluated and ZnO-carbon showed an enhancement in... 

    Study of the solubility of CO2, H2S and their mixture in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate: Experimental and modelling

    , Article Journal of Chemical Thermodynamics ; Volume 65 , 2013 , Pages 220-232 ; 00219614 (ISSN) Safavi, M ; Ghotbi, C ; Taghikhani, V ; Jalili, A. H ; Mehdizadeh, A ; Sharif University of Technology
    2013
    Abstract
    New experimental results are presented for the solubility of carbon dioxide, hydrogen sulfide in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]) at temperatures range from (303.15 to 353.15) K and pressures up to about 2 MPa. The solubility of the mixture of CO2/H2S in [C8mim][PF6] under various feed compositions were also measured at temperatures of (303.15, 323.15 and 343.15) K and the pressure up to 1 MPa. The solubility of carbon dioxide and hydrogen sulfide increased with increasing pressure and decreased with increasing temperature and the solubility of H2S is about three times that of CO2 in the particular ionic liquid studied. The measured data were... 

    Molybdenum liquid salts immobilized on ionic liquid-modified silica as efficient heterogeneous catalysts for sulfoxide reduction

    , Article Tetrahedron Letters ; Volume 54, Issue 29 , 2013 , Pages 3765-3768 ; 00404039 (ISSN) Bagherzadeh, M ; Ghazali Esfahani, S ; Sharif University of Technology
    2013
    Abstract
    Two room temperature liquid salts containing molybdenum(VI), [BMIM] 2[MoO2(NCS)4] (1) and [DMIM] 2[MoO2(NCS)4] (2), were immobilized on ionic liquid-modified silica leading to materials which showed notable catalytic activity for the reduction of sulfoxides into sulfides with triphenylphosphine (PPh3). The molybdenum liquid salts immobilized on the supported ionic liquid phase could be reused at least for three catalytic cycles without significant loss of activity  

    Synthesis, X-ray studies, DFT calculations and catalytic activity of a novel iron complex containing an N, O-type bidentate oxazine ligand

    , Article Polyhedron ; Volume 61 , 2013 , Pages 94-98 ; 02775387 (ISSN) Amini, M ; Haghdoost, M. M ; Bagherzadeh, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    The reactions of FeCl3·3H2O and 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N-O) as a bidentate O, N donor ligand afforded a five-coordinated iron(III) complex, [Fe(N-O) 2Cl], with a distorted trigonal bipyramidal configuration. The complex [Fe(N-O)2Cl] was isolated as an air-stable crystalline solid and was fully characterized, including by single-crystal X-ray structure analysis. The complex [Fe(N-O)2Cl] shows very efficient reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide (UHP) as the oxidant at room temperature under air. To get an insight into the electronic structure of the complex, the experimental studies have been accompanied... 

    Catalytic efficacy of an oxido-peroxido tungsten(VI) complex: Synthesis, X-ray structure and oxidation of sulfides and olefins

    , Article Journal of Coordination Chemistry ; Volume 66, Issue 11 , Jan , 2013 , Pages 1897-1905 ; 00958972 (ISSN) Amini, M ; Bagherzadeh, M ; Eftekhari Sis, B ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    An oxido-peroxido tungsten(VI) complex [WO(O2)L(CH 30H)] using salicylidene benzoyl hydrazine as a tridentate ONO donor Schiff base (H2L) has been synthesized and characterized by elemental analysis, IR, 1H NMR, molar conductance data, and single-crystal X-ray analysis. The complex was used as a catalyst for epoxidation of olefins and oxidation of sulfides. The results show that epoxides and sulfoxides were produced in high yield, turnover number, and selectivity  

    On the growth and photocatalytic activity of the vertically aligned ZnO nanorods grafted by CdS shells

    , Article Applied Surface Science ; Volume 273 , July , 2013 , Pages 391-398 ; 01694332 (ISSN) Zirak, M ; Moradlou, O ; Bayati, M. R ; Nien, Y. T ; Moshfegh, A. Z ; Sharif University of Technology
    2013
    Abstract
    We have studied systematically photocatalytic properties of the vertically aligned ZnO@CdS core-shell nanorods where the features were grown through a multistep procedure including sol-gel for the formation of ZnO seed layer, hydrothermal process to grow ZnO nanorods, and successive ion layer adsorption and reaction (SILAR) process to deposit CdS nanoshells onto the ZnO nanorods. Formation of the ZnO seed layer and vertically aligned ZnO nanorods (d ∼ 40 nm) with a hexagonal cross-section was confirmed by AFM and SEM imaging. Successful capping of ZnO nanorods with homogeneous CdS nanocrystallites (∼5 nm) was ascertained by HRTEM diffraction and imaging. Optical properties of the samples... 

    Spectrophotometric determination of sulfide based on peroxidase inhibition by detection of purpurogallin formation

    , Article Ecotoxicology and Environmental Safety ; Volume 91 , 2013 , Pages 117-121 ; 01476513 (ISSN) Ghadiri, M ; Kariminia, H. R ; Roosta Azad, R ; Sharif University of Technology
    2013
    Abstract
    This paper presents a new method for spectrophotometirc detection of sulfide applying fungal peroxidase immobilized on sodium alginate. The sensing scheme was based on decrease of the absorbance of the orange compound, purpurogallin produced from pyrogallol and H2O2 as substrates, due to the inhibition of peroxidase by sulfide. Absorbance of purpurogallin was detected at 420nm by using a spectrophotometer. The proposed method could successfully detect the sulfide in the concentration range of 0.6-7.0μM with a detection limit of 0.4μM. The kinetic parameters of Michaelis-Menten with and without sulfide were also calculated. Possible inhibition mechanism of peroxidase by sulfide was deduced... 

    Selective oxidation of sulfides and olefins by a manganese (III) complex containing an N,O-type bidentate oxazine ligand

    , Article Journal of Coordination Chemistry ; Volume 66, Issue 3 , 2013 , Pages 464-472 ; 00958972 (ISSN) Amini, M ; Bagherzadeh, M ; Moradi-Shoeili, Z ; Boghaei, D. M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    2013
    Abstract
    A new manganese(III) complex [(N-O)2Mn(OAc)] was synthesized using 2-(2'-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N-O) as a bidentate O, N donor. The complex has been characterized by elemental analysis, IR, UV-vis spectroscopy, and X-ray structure analysis. Oxidation of sulfides and epoxidation of olefins, respectively, to their corresponding sulfoxides and epoxides were conducted by this catalyst using urea hydrogen peroxide as oxidant at room temperature under air. The catalyst is efficient in oxidation reactions giving high yields and selectivities