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Total 141 records

    Transition metal ions-doped polyaniline/graphene oxide nanostructure as high performance electrode for supercapacitor applications

    , Article Journal of Solid State Electrochemistry ; 2017 , Pages 1-14 ; 14328488 (ISSN) Asen, P ; Shahrokhian, S ; Zad, A. I ; Sharif University of Technology
    Abstract
    Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless steel (SS) as the substrate. The Fe3+-Zn2+-PANI/GO nanocomposite is characterized using X-ray diffraction as well as Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Also, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy are used to study the electrochemical performance of the as-prepared electrode materials. Significantly, the Fe3+-Zn2+-PANI/GO nanocomposite exhibits a specific... 

    AgPt nanoparticles supported on magnetic graphene oxide nanosheets for catalytic reduction of 4-nitrophenol: studies of kinetics and mechanism

    , Article Applied Organometallic Chemistry ; Volume 31, Issue 11 , 2017 ; 02682605 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Abstract
    AgxPt100−x (x = 0, 25, 50, 75 and 100) nanoparticles were grown on the surface of magnetic graphene oxide nanosheets (Fe3O4@GO) for the first time. The as-prepared nanocomposites were characterized using various techniques such as Fourier transform infrared spectroscopy, powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, vibrating sample magnetometry and thermogravimetric analysis. The Fe3O4@GO-AgxPt100−x catalysts were applied in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol using sodium borohydride (NaBH4). The synthesized nanocomposites... 

    Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors

    , Article International Journal of Hydrogen Energy ; 2017 ; 03603199 (ISSN) Shahrokhian, S ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron... 

    Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors

    , Article International Journal of Hydrogen Energy ; Volume 43, Issue 4 , 2018 , Pages 2256-2267 ; 03603199 (ISSN) Shahrokhian, S ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron... 

    Highly sensitive nonenzymetic glucose sensing platform based on MOF-derived NiCo LDH nanosheets/graphene nanoribbons composite

    , Article Journal of Electroanalytical Chemistry ; Volume 808 , 2018 , Pages 114-123 ; 15726657 (ISSN) Asadian, E ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    Herein, a novel sensing platform based on NiCo layered double hydroxide (LDH) nanosheets/graphene nanoribbons (GNRs) modified glassy carbon electrode is presented for sensitive non-enzymetic determination of glucose. In the first step, nanoflower-like NiCo LDH nanosheets were grown on the surface of ZIF-67 dodecahedron nanocrystals which used as sacrificial template and were further characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD) and FTIR. In the next step, in order to fabricate a mechanically stable modified electrode, the as-prepared nanosheets were mixed with... 

    Transition metal ions-doped polyaniline/graphene oxide nanostructure as high performance electrode for supercapacitor applications

    , Article Journal of Solid State Electrochemistry ; Volume 22, Issue 4 , 2018 , Pages 983-996 ; 14328488 (ISSN) Asen, P ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
    Springer New York LLC  2018
    Abstract
    Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless steel (SS) as the substrate. The Fe3+-Zn2+-PANI/GO nanocomposite is characterized using X-ray diffraction as well as Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Also, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy are used to study the electrochemical performance of the as-prepared electrode materials. Significantly, the Fe3+-Zn2+-PANI/GO nanocomposite exhibits a specific... 

    Antibacterial properties of nanoporous graphene oxide/cobalt metal organic framework

    , Article Materials Science and Engineering C ; Volume 104 , 2019 ; 09284931 (ISSN) Hatamie, S ; Ahadian, M. M ; Soufi Zomorod, M ; Torabi, S ; Babaie, A ; Hosseinzadeh, S ; Soleimani, M ; Hatami, N ; Wei, Z. H ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Metal-organic framework (MOF) based graphene oxide (GO) recently merits of attention because of the relative correspondence of GO with metal ions and organic binding linkers. Furthermore, introducing the GO to the Co-MOF to make a new nanoporous hybrid have are improved the selectivity and stability of the Co-MOF. Here the graphene oxide/cobalt metal organic framework (GO/Co-MOF) was synthesized by a solvothermal process using cobalt salt and terephthalic acid and used for biocidal activity, against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy were confirmed... 

    Synthesis of nanostructured Ag@SiO2-Penicillin from high purity Ag NPs prepared by electromagnetic levitation melting process

    , Article Materials Science and Engineering C ; Volume 102 , 2019 , Pages 616-622 ; 09284931 (ISSN) Malekzadeh, M ; Yeung, K. L ; Halali, M ; Chang, Q ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Nanostructured Ag@SiO2-Penicillin was synthesized from high-purity Ag0 NPs with a mean particle size of about 10 nm produced by electromagnetic levitation gas condensation (ELGC) method. The silver and penicillin contents of the synthesized nano-antibiotic were about 34 wt% and 2.5 wt% respectively, as determined by ICP-OES and TGA analyses. The antibacterial properties and synergistic effects of nanostructured Ag@SiO2 and Ag@SiO2–Penicillin on killing the Methicillin-susceptible S. aureus (MSSA) and Methicillin-resistant S. aureus (MRSA) bacteria were also examined. The nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ag@SiO2-Penicillin... 

    Well-designed Ag/ZnO/3D graphene structure for dye removal: Adsorption, photocatalysis and physical separation capabilities

    , Article Journal of Colloid and Interface Science ; Volume 537 , 2019 , Pages 66-78 ; 00219797 (ISSN) Kheirabadi, M ; Samadi, M ; Asadian, E ; Zhou, Y ; Dong, C ; Zhang, J ; Moshfegh Zaker, A. R ; Sharif University of Technology
    Academic Press Inc  2019
    Abstract
    In this research, adsorption and photocatalytic degradation process were utilized to remove organic dye from wastewater. To accomplish that, a newly-designed ternary nanostructure based on Ag nanoparticles/ZnO nanorods/three-dimensional graphene network (Ag NPs/ZnO NRs/3DG) was prepared using a combined hydrothermal-photodeposition method. The three-dimensional structure of graphene hydrogel as a support for growth of ZnO nanorods was characterized using field emission scanning electron microscopy (FESEM). In addition, diameter of silver nanoparticles grown on the ZnO nanorods with the average aspect ratio of 5 was determined in the range of 30–80 nm by using transmission electron microscopy... 

    Synthesis, morpho-structural properties, and catalytic performances of Pt-APA@Fe3O4/GO nanocomposite based on magnetical graphene in C–C coupling reactions and photoinactivation of E. coli

    , Article Journal of Nanoparticle Research ; Volume 23, Issue 8 , 2021 ; 13880764 (ISSN) Moniriyan, F ; Sabounchei, S. J ; Yousefi, A ; Akhavan, O ; Sharif University of Technology
    Springer Science and Business Media B.V  2021
    Abstract
    Herein, a novel Pt-APA composite (APA = pyridinium bromide salt) based on magnetic graphene oxide was synthesized and used as an effective catalyst. In this way, Fe3O4 nanoparticles are grown on graphene oxide (GO) nanosheets by a simple and practical method which creates a unique nanostructure (Fe3O4/GO) through dispersing uniformly among graphene nanosheets. The resulted Pt-APA composite was obtained via adding PtCl2 to an ethanol solution of Fe3O4/GO and α-keto stabilized pyridinium ylide in related conditions. The synthesized nanocomposite structure was identified using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive... 

    Advancement in Fenton-like reactions using PVA coated calcium peroxide/FeS system: Pivotal role of sulfide ion in regenerating the Fe(II) ions and improving trichloroethylene degradation

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) Ali, M ; Zhang, X ; Idrees, A ; Tariq, M ; Danish, M ; Farooq, U ; Shan, A ; Jiang, X ; Huang, J ; Lyu, S ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    This study demonstrated the prolonged benefits of polyvinyl-coated calcium peroxide (PVA@CP) in Fe(II)/nFeS mediated Fenton-like reaction. PVA@CP was prepared by a coating of PVA on calcium peroxide (CP) and synthesized nano-sized iron sulfide (nFeS) was characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) elemental mapping, X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and Fourier transmission infrared (FTIR) techniques. Trichloroethylene (TCE) degradation in various oxic environments (H2O2, CP, or... 

    Advancement in Fenton-like reactions using PVA coated calcium peroxide/FeS system: Pivotal role of sulfide ion in regenerating the Fe(II) ions and improving trichloroethylene degradation

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) Ali, M ; Zhang, X ; Idrees, A ; Tariq, M ; Danish, M ; Farooq, U ; Shan, A ; Jiang, X ; Huang, J ; Lyu, S ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    This study demonstrated the prolonged benefits of polyvinyl-coated calcium peroxide (PVA@CP) in Fe(II)/nFeS mediated Fenton-like reaction. PVA@CP was prepared by a coating of PVA on calcium peroxide (CP) and synthesized nano-sized iron sulfide (nFeS) was characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) elemental mapping, X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and Fourier transmission infrared (FTIR) techniques. Trichloroethylene (TCE) degradation in various oxic environments (H2O2, CP, or... 

    Niosome-encapsulated tobramycin reduced antibiotic resistance and enhanced antibacterial activity against multidrug-resistant clinical strains of Pseudomonas aeruginosa

    , Article Journal of Biomedical Materials Research - Part A ; Volume 109, Issue 6 , 2021 , Pages 966-980 ; 15493296 (ISSN) Hedayati Ch, M ; Abolhassani Targhi, A ; Shamsi, F ; Heidari, F ; Salehi Moghadam, Z ; Mirzaie, A ; Behdad, R ; Moghtaderi, M ; Akbarzadeh, I ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Abstract
    In the current study, niosome-encapsulated tobramycin based on Span 60 and Tween 60 was synthesized and its biological efficacies including anti-bacterial, anti-efflux, and anti-biofilm activities were investigated against multidrug resistant (MDR) clinical strains of Pseudomonas aeruginosa. The niosomal formulations were characterized using scanning electron microscopy, transmission electron microscopy, and dynamic light scattering measurement. The encapsulation efficiency was found to be 69.54% ±; 0.67. The prepared niosomal formulations had a high storage stability to 60 days with small changes in size and drug entrapment, which indicates that it is a suitable candidate for pharmaceutical... 

    Toward visual chiral recognition of amino acids using a wide-range color tonality ratiometric nanoprobe

    , Article Analytica Chimica Acta ; Volume 1231 , 2022 ; 00032670 (ISSN) Jafar Nezhad Ivrigh, Z ; Fahimi Kashani, N ; Morad, R ; Jamshidi, Z ; Hormozi Nezhad, M. R ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Chiral recognition has long been a challenging issue to deal with in biological systems, drug design and food authentication. Implementing nanoparticle-based probes with intrinsic or induced chirality in this field has addressed several issues concerning sensitivity, reliability, rapidness and the cost of chiral sensing platforms. Yet, research into chiral nanoprobes that can be used for visual monitoring of chiral substances is still in its infancy. As part of this study, a visual chiral recognition platform has been developed in which a combination of blue-emitting carbon dots (BCDs) and mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs) with inherent chiroptical activity were... 

    A core–shell titanium dioxide polyaniline nanocomposite for the needle-trap extraction of volatile organic compounds in urine samples

    , Article Journal of Separation Science ; Volume 40, Issue 9 , 2017 , Pages 1985-1992 ; 16159306 (ISSN) Banihashemi, S ; Bagheri, H ; Sharif University of Technology
    Wiley-VCH Verlag  2017
    Abstract
    We synthesized a titanium dioxide–polyaniline core–shell nanocomposite and implemented it as an efficient sorbent for the needle-trap extraction of some volatile organic compounds from urine samples. Polyaniline was synthesized, in the form of the emeraldine base, dissolved in dimethyl acetamide followed by diluting with water at pH 2.8, using the interfacial polymerization method. The TiO2 nanoparticles were encapsulated inside the conducting polymer shell, by adapting the in situ dispersing approach. The surface characteristics of the nanocomposite were investigated by Fourier transform infrared spectrometry, scanning electron microscopy, and transmission electron microscopy. After... 

    Oxidation of toluene in humid air by metal oxides supported on Γ-alumina

    , Article Journal of Hazardous Materials ; Volume 333 , 2017 , Pages 293-307 ; 03043894 (ISSN) Esmaeilirad, M ; Zabihi, M ; Shayegan, J ; Khorasheh, F ; Sharif University of Technology
    Elsevier B.V  2017
    Abstract
    Monometallic and bimetallic supported metal oxides catalysts on γ-alumina were prepared by heterogeneous deposition-precipitation. The γ-alumina used as a support was synthesized by the sol-gel and the co-precipitation methods. Supports and catalysts were characterized by Brunauer–Emmett–Teller (BET) surface area, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The performance of the prepared catalysts was studied for total oxidation of toluene in air at different relative humidity and oxidation temperatures. Efficiency of bimetallic catalysts for deep oxidation of toluene was... 

    The field effect transistor DNA biosensor based on ITO nanowires in label-free hepatitis B virus detecting compatible with CMOS technology

    , Article Biosensors and Bioelectronics ; Volume 105 , 15 May , 2018 , Pages 58-64 ; 09565663 (ISSN) Shariati, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this paper the field-effect transistor DNA biosensor for detecting hepatitis B virus (HBV) based on indium tin oxide nanowires (ITO NWs) in label free approach has been fabricated. Because of ITO nanowires intensive conductance and functional modified surface, the probe immobilization and target hybridization were increased strongly. The high resolution transmission electron microscopy (HRTEM) measurement showed that ITO nanowires were crystalline and less than 50 nm in diameter. The single-stranded hepatitis B virus DNA (SS-DNA) was immobilized as probe on the Au-modified nanowires. The DNA targets were measured in a linear concentration range from 1fM to 10 µM. The detection limit of... 

    Comparison between electrochemical and photoelectrochemical detection of dopamine based on titania-ceria-graphene quantum dots nanocomposite

    , Article Biosensors and Bioelectronics ; Volume 151 , 2020 Ahmadi, N ; Bagherzadeh, M ; Nemati, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this study, titania-ceria-graphene quantum dot (TC-GQD) nanocomposite was synthesized by hydrothermal method for the first time. The prepared nanomaterials were characterized by XRD, FTIR dynamic light scattering (DLS), FESEM, HRTEM, and EDX spectroscopy along with elemental mapping. The synergistic effect of the nanocomposite components was studied by diffuse reflectance spectroscopy (DRS) and electrical conductivity meter. The results showed that band gap of TC-GQD nanocomposite was shifted to visible lights relative to its components (1.3 eV), and electrical conductivity of the sample was significant increased to 89.5 μS cm−1. After chemical and physical characterization, prepared new... 

    Biomimetic proteoglycan nanoparticles for growth factor immobilization and delivery

    , Article Biomaterials Science ; Volume 8, Issue 4 , 2020 , Pages 1127-1136 Zandi, N ; Mostafavi, E ; Shokrgozar, M. A ; Tamjid, E ; Webster, T. J ; Annabi, N ; Simchi, A ; Sharif University of Technology
    Royal Society of Chemistry  2020
    Abstract
    The delivery of growth factors is often challenging due to their short half-life, low stability, and rapid deactivation. In native tissues, the sulfated residual of glycosaminoglycan (GAG) polymer chains of proteoglycans immobilizes growth factors through the proteoglycans'/proteins' complexation with nanoscale organization. These biological assemblies can influence growth factor-cell surface receptor interactions, cell differentiation, cell-cell signaling, and mechanical properties of the tissues. Here, we introduce a facile procedure to prepare novel biomimetic proteoglycan nanocarriers, based on naturally derived polymers, for the immobilization and controlled release of growth factors.... 

    Immobilization of synthesized phenyl-enriched magnetic nanoparticles in a fabricated Y–Y shaped micro-channel containing microscaled hedges as a microextraction platform

    , Article Analytica Chimica Acta ; Volume 1136 , 2020 , Pages 51-61 Rezvani, O ; Hedeshi, M. H ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this survey, a reliable and applicable Y–Y shaped micro–channel in a microfluidic device was designed and manufactured. A number of micro–scaled hedges were precisely fabricated inside the micro–channel to facilitate the immobilization of synthesized core–shell Fe3O4@SiO2 magnetic nanoparticles (MNPs), functionalized by triethoxyphenylsilane (TEPS) by sol-gel technique. Both sample and reagents were introduced into the microfluidic device by a syringe pump to perform the extraction and desorption steps. The functionalized MNPs were characterized by transmission electron microscopy, X-ray diffraction spectroscopy and Fourier transform infrared spectroscopy. By adopting the strategy of...