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    Removal of toxic metal ions from sungun acid rock drainage using mordenite zeolite, graphene nanosheets, and a novel metal–organic framework

    , Article Mine Water and the Environment ; Volume 35, Issue 1 , 2016 , Pages 18-28 ; 10259112 (ISSN) Rahimi, E ; Mohaghegh, N ; Sharif University of Technology
    Springer Verlag  2016
    We evaluated the sorptive properties of mordenite zeolite (MOR), a copper terephthalate metal–organic framework (MOF), and graphene oxide (GO) and their potential use in treating acid rock drainage (ARD) containing Fe3+, Cu2+, Mn2+, Zn2+, Pb2+, and Cd2+ ions. MOR was prepared via a hydrothermal method, MOF was prepared via a solvothermal method, and few-layered GO nanosheets were synthesized using Hummers’ method. The aqueous contaminants were removed by chemico-physical sorption and ion exchange in batch tests. It proved possible to dramatically improve removal efficiency and sorptive capacity by optimizing experimental conditions. Magnetic MOF crystals were more efficient in removing... 

    Immobilization of dioxomolybdenum(VI) schiff base complex on graphene oxide nanosheets and its catalytic activity for oxidation of sulfides

    , Article Journal of Coordination Chemistry ; Volume 70, Issue 17 , 2017 , Pages 2986-2998 ; 00958972 (ISSN) Bagherzadeh, M ; Karimi, H ; Amini, M ; Sharif University of Technology
    Graphene oxide was an effective supporting material for immobilizing a dioxomolybdenum Schiff base complex via covalent interaction. The large surface of graphene oxide plays important roles to obtain a good degree of catalytic reaction. Catalytic capacity of the graphene-bound dioxomolybdenum Schiff base complex was investigated for the oxidation of various sulfides to sulfoxide compounds using hydrogen peroxide urea as an oxidant. The catalyst was characterized by various techniques including XRD, FTIR, TGA, SEM, UV–vis, and ICP-AES. The immobilized complex was very efficient with the extra benefits of easy recovery and recycling of the heterogeneous catalyst. The graphene oxide bound... 

    Fabrication of chitosan/poly(lactic acid)/graphene oxide/TiO2 composite nanofibrous scaffolds for sustained delivery of doxorubicin and treatment of lung cancer

    , Article International Journal of Biological Macromolecules ; 2017 ; 01418130 (ISSN) Samadi, S ; Moradkhani, M ; beheshti, H ; Irani, M ; Aliabadi, M ; Sharif University of Technology
    Elsevier B.V  2017
    In this work, the synthesized graphene oxide/TiO2/doxorubicin (GO/TiO2/DOX) composites were loaded into the chitosan/poly(lactic acid) (PLA) solutions to fabricate the electrospun chitosan/PLA/GO/TiO2/DOX nanofibrous scaffolds via electrospinning process. The synthesized composites and nanofibers were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. Three-factor three-level central composite design was used to determine the influence of PLA to chitosan ratio, TiO2/DOX content and GO/TiO2/DOX content on the release of DOX from nanofibrous scaffolds. Drug loading efficiency and drug release behavior from... 

    Carbon black-intercalated reduced graphene oxide electrode with graphene oxide separator for high-performance supercapacitor

    , Article Journal of Nanostructures ; Volume 9, Issue 4 , 2019 , Pages 639-649 ; 22517871 (ISSN) Jeddi, H ; Rasuli, R ; Ahadian, M. M ; Mehrabi, B ; Sharif University of Technology
    University of Kashan  2019
    We present a general study on a high performance supercapacitor based on intercalated reduced graphene oxide with carbon black nanoparticles. Graphene oxide sheets were synthesized by oxidation and exfoliation of natural graphite and were reduced using hydroiodic acid in the presence of carbon black nanoparticles. Graphene paper was fabricated by one-step procedure via simultaneous reducing and drying the aqueous solution of mixed carbon black nanoparticles and graphene oxide on a conductive substrate. Transmission electron microscopy confirmed the intercalation of carbon black nanoparticles into reduced graphene oxide sheets, preventing them from restacking during the fabrication of paper.... 

    Cysteic acid grafted to magnetic graphene oxide as a promising recoverable solid acid catalyst for the synthesis of diverse 4H-chromene

    , Article Scientific Reports ; Volume 10, Issue 1 , December , 2020 Matloubi Moghaddam, F ; Eslami, M ; Hoda, G ; Sharif University of Technology
    Nature Research  2020
    4H-chromenes play a significant role in natural and pharmacological products. Despite continuous advances in the synthesis methodology of these compounds, there is still a lack of a green and efficient method. In this study, we have designed cysteic acid chemically attached to magnetic graphene oxide (MNPs·GO-CysA) as an efficient and reusable solid acid catalyst to synthesize 4H-chromene skeletons via a one-pot three components reaction of an enolizable compound, malononitrile, an aldehyde or isatin, and a mixture of water–ethanol as a green solvent. This new heterogeneous catalyst provides desired products with a good to excellent yield, short time, and mild condition. This procedure... 

    Enhancement of self-powered humidity sensing of graphene oxide–based triboelectric nanogenerators by addition of graphene oxide nanoribbons

    , Article Microchimica Acta ; Volume 188, Issue 8 , 2021 ; 00263672 (ISSN) Ejehi, F ; Mohammadpour, R ; Asadian, E ; Fardindoost, S ; Sasanpour, P ; Sharif University of Technology
    Springer  2021
    A triboelectric nanogenerator (TENG) electrode sensitive to the adsorption of water molecules has been introduced to create a self-powered humidity sensor. Graphene oxide (GO) nanosheets and graphene oxide nanoribbon (GONR) possessing oxygenated functional groups, as well as high dielectric constants, have been proposed as appropriate candidates for this purpose. GO papers have been fabricated in three forms, i.e. pure GO paper, uniform composites of GONR and GO, and double-layer structures of GONR on top of GO. Results showed that all of the prepared paper-based TENGs revealed excellent performances by maximum output voltage above 300 V. As active humidity sensors, the maximum voltage... 

    Pd-WO3/reduced graphene oxide hierarchical nanostructures as efficient hydrogen gas sensors

    , Article International Journal of Hydrogen Energy ; Volume 39, Issue 15 , 15 May , 2014 , Pages 8169–8179 Esfandiara, A. (Ali) ; Iraji Zada, A. (Azam) ; Akhavana, O. (Omid) ; Ghasemic, S. (Shahnaz) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Pd–WO3 nanostructures were incorporated on graphene oxide (GO) and partially reduced graphene oxide (PRGO) sheets using a controlled hydrothermal process to fabricate effective hydrogen gas sensors. Pd–WO3 nanostructures showed ribbon-like morphologies and Pd–WO3/GO presented an irregular nanostructured form, while Pd–WO3/PRGO exhibited a hierarchical nanostructure with a high surface area. Gas sensing properties of thin films of these materials were studied for different hydrogen concentrations (from 20 to 10,000 ppm) at various temperatures (from room temperature to 250 °C). Although adding GO in the Pd–WO3, after hydrothermal process could increase the film conductivity, gas sensitivity... 

    Ionic liquid/graphene oxide as a nanocomposite for improving the direct electrochemistry and electrocatalytic activity of glucose oxidase

    , Article Journal of Solid State Electrochemistry ; Vol. 17, Issue 1 , January , 2013 , pp 183-189 ; ISSN: 1432-8488 Tasviri, M (Mahboubeh) ; Ghasemi, S. (Shahnaz) ; Ghourchian, H. (Hedayatollah) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    By combination of 1-ethyl-3-methyl immidazolium ethyl sulfate as a typical room temperature ionic liquid (IL) and graphene oxide (GO) nanosheets, a nanocomposite was introduced for improving the direct electrochemistry and electrocatalytic activity of glucose oxidase (GOx). The enzyme on the IL–GO-modified glassy carbon electrode exhibited a quasireversible cyclic voltammogram corresponding to the flavine adenine dinucleotide/FADH2 redox prosthetic group of GOx. At the scan rate of 100 mV s−1, the enzyme showed a peak-to-peak potential separation of 82 mV and the formal potential of −463 mV (vs Ag/AgCl in 0.1 M phosphate buffer solution, pH 7.0). The kinetic parameters of the charge transfer... 

    Fabrication and characterization of a polysulfone-graphene oxide nanocomposite membrane for arsenate rejection from water

    , Article Journal of Environmental Health Science and Engineering ; Volume 13, Issue 1 , 2015 ; 2052336X (ISSN) Rezaee, R ; Nasseri, S ; Mahvi, A. H ; Nabizadeh, R ; Mousavi, S. A ; Rashidi, A ; Jafari, A ; Nazmara, S ; Sharif University of Technology
    BioMed Central Ltd  2015
    Background: Nowadays, study and application of modified membranes for water treatment have been considered significantly. The aim of this study was to prepare and characterize a polysulfone (PSF)/graphene oxide (GO) nanocomposite membrane and to evaluate for arsenate rejection from water. Materials and methods: The nanocomposite PSF/GO membrane was fabricated using wet phase inversion method. The effect of GO on the synthesized membrane morphology and hydrophilicity was studied by using FE-SEM, AFM, contact angle, zeta potential, porosity and pore size tests. The membrane performance was also evaluated in terms of pure water flux and arsenate rejection. Results: ATR-FTIR confirmed the... 

    Enhanced thermal stability and biocompatibility of gold nanorods by graphene oxide

    , Article Plasmonics ; 2017 , Pages 1-10 ; 15571955 (ISSN) Shirshahi, V ; Hatamie, S ; Tabatabaei, S. N ; Salimi, M ; Saber, R ; Sharif University of Technology
    In the present study, the effect of nanosized graphene oxide layer on thermal stability and biocompatibility of gold nanorods has been examined. The graphene oxide-wrapped gold nanorods were prepared by electrostatic interaction between negatively charged graphene oxide and positively charged nanorods. The resulting nanohybrids were then heated at different time intervals to 95 °C in a water bath to assess the effect of heat on the rods morphology. The structural changes in gold nanorods were monitored via UV-Vis spectroscopy measurements and transmission electron microscopy images. In similar experiments, the graphene oxide used to wrap gold nanorods was reduced by ascorbic acid in a 95 °C... 

    Evaluation of dosimetric characteristics of graphene oxide/PVC nanocomposite for gamma radiation applications

    , Article Radiochimica Acta ; Volume 105, Issue 2 , 2017 , Pages 161-170 ; 00338230 (ISSN) Feizi, S ; Malekie, S ; Rahighi, R ; Tayyebi, A ; Ziaie, F ; Sharif University of Technology
    Walter de Gruyter GmbH  2017
    Graphene oxide-polyvinyl chloride composite was prepared using tetrahydrofuran solvent-assisted dispersion of characterized nano flakes of graphene oxide in polymer matrix. Electrical percolation threshold of GO/PVC nanocomposite was determined via a finite element simulation method with a 2D model and compared with experimental results. A conductive cell with two silver coated walls was designed and fabricated for exploring dosimetric properties of the composite. Some characteristics of the new nanocomposite such as linearity of dose response, repeatability, sensitivity and angular dependence are investigated. According to 2D proposed method, obtained data associated to electrical... 

    Optimizing carbonaceous nanostructure composition as a substrate to grow co electrocatalysts

    , Article Iranian Journal of Physics Research ; Volume 17, Issue 5 , 2018 , Pages 753-760 ; 16826957 (ISSN) Pourreza, M ; Naseri, N ; Ghasemi, S ; Sharif University of Technology
    Isfahan University of Technology  2018
    Global warming and other adverse environmental effects of fossil fuels have forced humans to consider clean and renewable energy resources. In this context, hydrogen production from water splitting reaction is a key approach. In order to reduce required overpotential for water oxidation reaction, it is necessary to use low cost and earth abundant electrocatalysts like Co, Cu, Fe, Mn, Ni and Zn nanostructures. Herein, cobalt nanostructures on steel-mesh substrate were applied. Electrochemical method was used for growth of Co nanoflakes because of its simplicity and scalability for commercial approach. On the other hand, using carbonaceous support layers including nanomaterials such as... 

    Enhanced thermal stability and biocompatibility of gold nanorods by graphene oxide

    , Article Plasmonics ; Volume 13, Issue 5 , 2018 , Pages 1585-1594 ; 15571955 (ISSN) Shirshahi, V ; Hatamie, S ; Tabatabaei, S. N ; Salimi, M ; Saber, R ; Sharif University of Technology
    In the present study, the effect of nanosized graphene oxide layer on thermal stability and biocompatibility of gold nanorods has been examined. The graphene oxide-wrapped gold nanorods were prepared by electrostatic interaction between negatively charged graphene oxide and positively charged nanorods. The resulting nanohybrids were then heated at different time intervals to 95 °C in a water bath to assess the effect of heat on the rods morphology. The structural changes in gold nanorods were monitored via UV-Vis spectroscopy measurements and transmission electron microscopy images. In similar experiments, the graphene oxide used to wrap gold nanorods was reduced by ascorbic acid in a 95 °C... 

    A novel nanocomposite with superior antibacterial activity: a silver-based metal organic framework embellished with graphene oxide

    , Article Advanced Materials Interfaces ; Volume 5, Issue 11 , 3 April , 2018 ; 21967350 (ISSN) Dadashi Firouzjaei, M ; Arabi Shamsabadi, A ; Sharifian Gh, M ; Rahimpour, A ; Soroush, M ; Sharif University of Technology
    Wiley-VCH Verlag  2018
    Silver-based nanomaterials have attracted considerable attention due to their antimicrobial activities. In this work, a silver (Ag)-based metal organic framework (Ag-MOF) is embellished with graphene-oxide (GO), leading to the fabrication of a novel Ag-based nanocomposite (GO-Ag-MOF) whose biocidal activity is higher than those of Ag-MOF and GO nanomaterials. The nanocomposite is characterized using X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscope, Fourier transform infrared spectra, ultraviolet−visible absorption spectra, X-ray powder diffraction, dynamic light scattering, and nitrogen gas adsorption/desorption. The characterization shows that... 

    Thin film graphene oxide membrane: challenges and gas separation potential

    , Article Korean Journal of Chemical Engineering ; Volume 35, Issue 5 , May , 2018 , Pages 1174-1184 ; 02561115 (ISSN) Abbasi, F ; Karimi Sabet, J ; Ghotbi, C ; Abbasi, Z ; Sharif University of Technology
    Springer New York LLC  2018
    Graphene oxide membranes were prepared by vacuum and pressurized ultrafiltration methods on the 12% modified Polyacrylonitrile (12mPAN) substrate to specify challenges, salient features, future directions, and potential of GO membrane for separation fields using characterization techniques and gas separation test (studied gases are CO2, He and N2), which is an efficient tool for better understanding of GO membrane behavior. GO membrane structure was examined over a wide range of parameters, such as pore size range of substrate and its surface properties, pH of GO dispersion, GO content, synthesis pressure, operating pressure and temperature. The results show that the GO content does not hold... 

    Photoluminescence and electrochemical investigation of curcumin-reduced graphene oxide sheets

    , Article Journal of the Iranian Chemical Society ; Volume 15, Issue 2 , February , 2018 , Pages 351-357 ; 1735207X (ISSN) Hatamie, S ; Ahadian, M. M ; Iraji zad, A ; Akhavan, O ; Jokar, E ; Sharif University of Technology
    Springer Verlag  2018
    This paper reports on a novel low-temperature method for preparing curcumin-reduced graphene oxide (Cur-rGO) from graphene oxide (GO) and investigates their cyclic voltammetry (CV) and photoluminescence (PL) properties. GO sheets were synthesized using modified Hummers’ method and then were chemically reduced using polyphenol curcumin into graphene sheets. Atomic force microscopy, transmission electron microscopy and x-ray photoelectron spectroscopy were used to confirm the formation of Cur-rGO and revealed their functionalization with polyphenol curcumin. The electrochemical and optical properties of the Cur-rGO sheets were investigated using CV and PL spectroscopy. According to the PL and... 

    A new SnS2-BiFeO3/reduced graphene oxide photocatalyst with superior photocatalytic capability under visible light irradiation

    , Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 359 , 2018 , Pages 11-22 ; 10106030 (ISSN) Bagherzadeh, M ; Kaveh, R ; Sharif University of Technology
    Elsevier B.V  2018
    Herein, we report the preparation of SnS2 nanoflakes decorated with bismuth ferrite (BiFeO3) nanoparticles and reduced graphene oxide (rGO) nanosheets. The crystal structures and morphology results of composite indicated that spherical BiFeO3 nanoparticles were homogeneously attached onto the surface of SnS2 nanoflakes with the decoration of rGO sheets. The optimized photocatalyst, i.e. SnS2 (1.5)-BiFeO3/rGO (0.15) composite not only exhibites the highest photocatalytic performance for the degradation of methylene blue (MB) and Methyl orange (MO) as model reaction under visible light illumination among the individual SnS2 and BiFeO3 photocatalysts but also retains the stable photodegradation... 

    Polyacrylamide-grafted magnetic reduced graphene oxide nanocomposite: preparation and adsorption properties

    , Article Colloid and Polymer Science ; 2019 ; 0303402X (ISSN) Pourjavadi, A ; Nazari, M ; Kohestanian, M ; Hosseini, S. H ; Sharif University of Technology
    Springer Verlag  2019
    Magnetic reduced graphene oxide/polymer nanocomposites were prepared by in situ polymerization and grafting of polyacrylamide on the surface of functionalized magnetic reduced graphene oxide (rGO). Graphene oxide nanosheets were decorated with Fe3O4 nanoparticles, reduced and functionalized with 3-(trimethoxysilyl)propyl methacrylate, and then grafted with polyacrylamide. Grafting of polyacrylamide makes magnetic rGO hydrophilic and highly water dispersible. The prepared material was used as adsorbent for removal of an anionic dye, Congo red, and a maximum adsorption capacity up to 166.7 mg g−1 was obtained. The kinetics and isotherm of adsorption and the effect of experimental condition on... 

    Recent developments in graphene and graphene oxide: properties, synthesis, and modifications: a review

    , Article ChemistrySelect ; Volume 5, Issue 33 , 2020 , Pages 10200-10219 Farjadian, F ; Abbaspour, S ; Abdolahi Sadatlu, M. A ; Mirkiani, S ; Ghasemi, A ; Hoseini Ghahfarokhi, M ; Mozaffari, N ; Karimi, M ; Hamblin, M. R ; Sharif University of Technology
    Wiley-Blackwell  2020
    Graphene was first discovered as a sheet structure mechanically exfoliated from a block of graphite, but in recent years researchers have extended their investigations into this two-dimensional carbon nanostructure. Various applications of graphene-based materials have included electronics, photonics, optoelectronics, sensors, and drug / gene delivery systems. These single atom carbon layers have the potential to be formed in different morphologies e. g., quantum dots, nanosheets, and nanoparticles, which can be tailored to achieve new breakthrough innovations. Nowadays, the utilization of graphene-based nanomaterials in medicine is a hot research topic. This review discusses the structure,... 

    Magnetically recoverable TiO2/SiO2/γ-Fe2O3/rGO composite with significantly enhanced UV-visible light photocatalytic activity

    , Article Molecules ; Volume 25, Issue 13 , 2020 Kaveh, R ; Mokhtarifar, M ; Bagherzadeh, M ; Lucotti, A ; Diamanti, M. V ; Pedeferri, M ; Sharif University of Technology
    MDPI AG  2020
    In this paper, we report the preparation of a new composite (TiO2/SiO2/γ-Fe2O3/rGO) with a high photocatalytic efficiency. The properties of the composite were examined by different analyses, including X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), photoluminescence (PL), UV-Visible light diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy (FTIR), Raman, vibrating-sample magnetometer (VSM), and nitrogen gas physisorption (BET) studies. The photocatalytic efficiency of the proposed composite was evaluated by the degradation of methylene blue under UV and visible light, and the results were compared with titanium dioxide (TiO2), where...