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Preparation, magnetic properties, and photocatalytic performance under natural daylight irradiation of Fe3O4-ZnO core/shell nanoparticles designed on reduced go platelet
, Article Materials Science in Semiconductor Processing ; Volume 72 , 2017 , Pages 85-92 ; 13698001 (ISSN) ; Baghshahi, S ; Nemati, A ; Mahmoodi, M ; Sharif University of Technology
Abstract
Ternary mesoporous nanocomposites of RGO/Fe3O4-ZnO were prepared successfully via hydrothermal technique. Fe3O4-ZnO core/shell nanoparticles were decorated on the surface of reduced graphene oxide platelet to improve charge separation efficiency and magnetic properties. The phase, microstructure and specific surface area of the prepared samples were determined via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy/selected area electron diffraction (TEM/SAED) and Brunauer–Emmett–Teller (BET) techniques. A vibrating sample magnetometer (VSM) was used for recording the magnetization hysteresis curves. The methylene blue (MB)...
Turning toxic nanomaterials into a safe and bioactive nanocarrier for co-delivery of DOX/pCRISPR
, Article ACS Applied Bio Materials ; Volume 4, Issue 6 , 2021 , Pages 5336-5351 ; 25766422 (ISSN) ; Bagherzadeh, M ; Ghadiri, A. M ; Fatahi, Y ; Aldhaher, A ; Makvandi, P ; Dinarvand, R ; Jouyandeh, M ; Saeb, M. R ; Mozafari, M ; Shokouhimehr, M ; Hamblin, M. R ; Varma, R. S ; Sharif University of Technology
American Chemical Society
2021
Abstract
Hybrid bioactive inorganic-organic carbon-based nanocomposites of reduced graphene oxide (rGO) nanosheets enlarged with multi-walled carbon nanotubes (MWCNTs) were decorated to provide a suitable space forin situgrowth of CoNi2S4and green-synthesized ZnO nanoparticles. The ensuing nanocarrier supplied π-π interactions between the DOX drug and a stabilizing agent derived from leaf extracts on the surface of ZnO nanoparticles and hydrogen bonds; gene delivery of (p)CRISPR was also facilitated by chitosan and alginate renewable macromolecules. Also, these polymers can inhibit the potential interactions between the inorganic parts and cellular membranes to reduce the potential cytotoxicity....
Scalable, microwave-assisted decoration of commercial cotton fabrics with binary nickel cobalt sulfides towards textile-based energy storage
, Article Electrochimica Acta ; Volume 404 , 2022 ; 00134686 (ISSN) ; Balim, U ; Unalan, H. E ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
High-performance textile-based energy storage systems with high energy and power densities alongside remarkable cyclic life are always at the leading edge of wearable electronics. Herein, commercial cotton fabrics (CCFs) are used as the substrates for the fabrication of ultra-light, high-performance wearable supercapacitors. Hierarchical microstructures of nickel-cobalt sulfide (Ni-Co-S) decorated single-walled carbon nanotubes (SWCNTs) are used as the positive supercapacitor electrodes. Enhanced electrochemical performance with a specific gravimetric capacity of 331 Cg−1 (at a current density of 0.3 Ag−1) is obtained from these Ni-Co-S@SWCNT@CCF electrodes. Besides, composites of graphene...
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) ; 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) ; 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...
Comprehensive Study of an Ag@Pt Core–shell Nanoparticles Supported on Carbon Structure in a Proton Exchange Membrane Fuel Cell
, Ph.D. Dissertation Sharif University of Technology ; Kazemeini, Mohammad (Supervisor) ; Bastani, Dariush (Supervisor)
Abstract
Core-shell structures of Ag@Pt nanoparticles (NPs) dispersed on Carbon Vulcan XC-72, Multiwalled carbon nanotube and reduced graphene oxide (rGO) support containing different Ag:Pt mass ratios and applied to the oxygen reduction reaction (ORR) in a proton exchange membrane fuel cell (PEMFC) were synthesized by the ultrasonic and reduction treatment method. The morphology of as-prepared catalysts characterized by the high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and induced coupled plasma atomic emission spectroscopy (ICP-OES). The ORR activities and stabilities of catalysts were studied through electrochemical measurements utilizing the Cyclic Voltammetry...
Study of Photovoltaic Characteristics of Prepared Titanium Oxide-reduced Graphene Oxide Nanocomposite as Photoanode of Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
In the present study, TiO2-reduced graphene oxide (T-RGO) nanocomposites were synthesized via various in-situ and ex-situ methods, then their photovoltaic performance was examined as photoanode and mesoporous layers in dye-sensitized Solar Cells (DSSCs) and perovskite Solar Cells (PSCs), respectively. Graphene oxide (GO) was prepared using Hummer’s method with some modifications. Both thermal and hydrothermal processes were used to reduce GO. Structural and optical characterization was analytically demonstrated by subjecting of the obtained materials by several techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman, thermogravimetric analysis (TGA),...
Study on the Performance of Magnetic Nanoparticles in Hyper-thermic Treatment of Cancerous Tumors, by Heating an MRI Apparatus
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Nourani, Mohammad Reza (Supervisor)
Abstract
The aim of this study was to investigate the rate of increase in temperature of a phantom equivalent to body tissue by different groups of magnetic iron nanoparticles in the external magnetic field to kill cancer cells based on the hyperthermia method. To achieve this goal, three groups of dextran magnetic nanoparticles with different properties and reduced iron oxide-graphene oxide magnetic nanoparticles by M-rGO supercritical synthesis method were used. After XRD, FTIR, SEM, FESEM, VSM, TEM characterization tests, these materials were placed in a phantom made of agarose gel and with the same properties, in a magnetic field with fixed characteristics for all groups and during the process of...
Nickel hydroxide nanoparticles-reduced graphene oxide nanosheets film: Layer-by-layer electrochemical preparation, characterization and rifampicin sensory application
, Article Talanta ; Vol. 119 , 2014 , pp. 156-163 ; ISSN: 00399140 ; Shahrokhian, S ; Sharif University of Technology
Abstract
Electrochemical deposition, as a well-controlled synthesis procedure, has been used for subsequently layer-by-layer preparation of nickel hydroxide nanoparticle-reduced graphene oxide nanosheets (Ni(OH)2-RGO) on a graphene oxide (GO) film pre-cast on a glassy carbon electrode surface. The surface morphology and nature of the nano-hybrid film (Ni(OH)2-RGO) was thoroughly characterized by scanning electron and atomic force microscopy, spectroscopy and electrochemical techniques. The modified electrode appeared as an effective electro-catalytic model for analysis of rifampicin (RIF) by using linear sweep voltammetry (LSV). The prepared modified electrode exhibited a distinctly higher activity...
Genotoxicity of graphene nanoribbons in human mesenchymal stem cells
, Article Carbon ; Volume 54 , 2013 , Pages 419-431 ; 00086223 (ISSN) ; Ghaderi, E ; Emamy, H ; Akhavan, F ; Sharif University of Technology
2013
Abstract
Single-layer reduced graphene oxide nanoribbons (rGONRs) were obtained through an oxidative unzipping of multi-walled carbon nanotubes and a subsequent deoxygenation by hydrazine and bovine serum albumin. Human mesenchymal stem cells (hMSCs) were isolated from umbilical cord blood and used for checking the concentration- and time-dependent cyto- and geno-toxic effects of the rGONRs and reduced graphene oxide sheets (rGOSs). The cell viability assay indicated significant cytotoxic effects of 10 μg/mL rGONRs after 1 h exposure time, while the rGOSs exhibited the same cytotoxicity at concentration of 100 μg/mL after 96 h. The oxidative stress was found as the main mechanism involved in the...
Nontoxic concentrations of PEGylated graphene nanoribbons for selective cancer cell imaging and photothermal therapy
, Article Journal of Materials Chemistry ; Volume 22, Issue 38 , 2012 , Pages 20626-20633 ; 09599428 (ISSN) ; Ghaderi, E ; Emamy, H ; Sharif University of Technology
2012
Abstract
Reduced graphene oxide nanoribbons functionalized by amphiphilic polyethylene glycol (rGONR-PEG) were applied to attach arginine-glycine-aspartic acid (RGD)-based peptide and cyanine dye 3 (cy3) for targeting ανβ3 integrin receptors on human glioblastoma cell line U87MG and its selective fluorescence imaging, respectively. The rGONR-PEG suspension with a concentration of 100 μg mL -1 showed ∼14 and 2.4-fold higher near infrared (NIR) absorption at 808 nm than GONR (with dimensions of ∼80 nm × 1 μm) and rGO-PEG sheets (with lateral dimensions of ∼2 μm), respectively. The rGONR-PEG-cy3-RGD exhibited highly efficient NIR photothermal therapy performance (concentrations ≥1.0 μg mL-1 resulted in...
Preparation of PVA nanocomposites using salep-reduced graphene oxide with enhanced mechanical and biological properties
, Article RSC Advances ; Volume 5, Issue 112 , 2015 , Pages 92428-92437 ; 20462069 (ISSN) ; Pourbadiei, B ; Doroudian, M ; Azari, S ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Salep, known as a biodegradable polysaccharide, is hydrolyzed and used as both a reducing agent and stabilizer for graphene oxide (GO). The functionalized reduced graphene oxide (f-rGO) is homogenously dispersed in an aqueous solution of poly(vinyl alcohol) (PVA). PVA based hydrogel and film nanocomposites are prepared and proposed as new biomaterials for tissue engineering applications. The mechanical properties of the film nanocomposites are investigated with varying content of f-rGO, glycerol and citric acid as a reinforcing agent, a plasticizer agent and a cross linking agent respectively. For the first time, chemically cross linked PVA hydrogels are synthesized using...
Ball mill assisted synthesis of Na3MnCO3PO4 nanoparticles anchored on reduced graphene oxide for sodium ion battery cathodes
, Article Electrochimica Acta ; Volume 220 , 2016 , Pages 683-689 ; 00134686 (ISSN) ; Sadrnezhaad, S. K ; Chen, G ; Sharif University of Technology
Elsevier Ltd
Abstract
Na3MnCO3PO4 (NMCP) particles were synthesized via ball milling of Mn(NO3)2.4H2O, Na2HPO4.2H2O and Na2CO3.H2O powders. The particles were anchored onto reduced graphene oxide (rGO) sheets during hydrothermal reduction process under stirring. Materials produced were characterized by x-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric (TG) measurement and galvanostatic charge/discharge tests. Results showed that dissolution of ball milling products in DI water is an effective method for separation of NMCP from byproducts. Best milling time for production of pure NMCP of minimum particle...
Impact of preparation method of TiO2-RGO nanocomposite photoanodes on the performance of dye-sensitized solar cells
, Article Electrochimica Acta ; Volume 219 , 2016 , Pages 38-48 ; 00134686 (ISSN) ; Mohammadi, M. R ; Lianos, P ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
In this work, a comparative study has been performed on two ex-situ and one in-situ doping of titania photoanodes with reduced graphene oxide. The presence of finely dispersed reduced graphene oxide facilitates electron transport and reduces electron-hole recombination resulting in a better performance of doped titania photoanodes. It was found that in-situ doping, i.e. introduction of graphene oxide in solution together with titania precursor was the most performant case of graphene doping. This result was obvious by studying dye-sensitized solar cells based on such doped photoanodes but was also and mainly analytically demonstrated by subjecting the obtained materials to characterization...
Supercritical synthesis of a magnetite-reduced graphene oxide hybrid with enhanced adsorption properties toward cobalt & strontium ions
, Article RSC Advances ; Volume 6, Issue 17 , 2016 , Pages 13898-13913 ; 20462069 (ISSN) ; Outokesh, M ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
The current study presents a supercritical synthesis of magnetite-reduced graphene oxide (M-RGO) in methanol media, in which Fe3O4 nanoparticles are simultaneously formed, surface modified and decorated on the surface of the reduced graphene oxide. Simulations using density functional theory, which were performed using the M06-2x/cc-pVDZ level of theory, indicate that upon adsorption of a Fe3O4 cluster on the graphene, the overall charge on the graphene surface becomes about -0.0236e, indicating charge transfer from the Fe3O4 cluster to the graphene surface. Instrumental and chemical analyses exhibited the formation of strong bonds between Fe3O4 and graphene, through C-O-Fe and C-Fe bridges....
BiPO4 photocatalyst employing synergistic action of Ag/Ag3PO4 nanostructure and graphene nanosheets
, Article Solid State Sciences ; Volume 56 , 2016 , Pages 10-15 ; 12932558 (ISSN) ; Rahimi, E ; Sharif University of Technology
Elsevier Masson SAS
Abstract
Graphene-supported BiPO4/Ag/Ag3PO4 photocatalyst has been fabricated by simple hydrothermal and impregnation reaction. In BiPO4/Ag/Ag3PO4 based on Reduced Graphene Oxide (RGO), this network renders numerous pathways for rapid mass transport, strong adsorption and multireflection of incident light; meanwhile, the interface between BiPO4/Ag/Ag3PO4 and RGO increases the active sites and electron transfer rate. BiPO4/Ag/Ag3PO4 based on RGO noticeably exhibited high photocatalytic activity than that of BiPO4/Ag/Ag3PO4 and P25 under visible light irradiation for cationic dye (Rhodamine B), anionic dye (methyl orange) and 4-chlorophenol (4-CP) as a neutral pollutant, which are usually difficult to...
Simultaneous electrodeposition of reduced graphene oxide/ag nanoparticles as a sensitive layer for voltammetric determination of tinidazole
, Article Nano ; Volume 12, Issue 6 , 2017 ; 17932920 (ISSN) ; Navabi, M ; Mohammadi, R ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2017
Abstract
A stable composite film of silver nanoparticles (Ag NPs) decorated on reduced graphene oxide is prepared by a two-step simple procedure. The surface morphology of the modified electrode is characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The electrochemical behavior of tinidazole (TNZ) on the surface of the modified electrode is investigated by linear sweep voltammetry and electrochemical impedance spectroscopy. The prepared composite electrode acts as a highly sensitive platform for the voltammetric determination of TNZ, leading to a significant increase in the reduction peak current of TNZ. The effects of experimental parameters such as the...
Apoptotic and anti-apoptotic genes transcripts patterns of graphene in mice
, Article Materials Science and Engineering C ; Volume 71 , 2017 , Pages 460-464 ; 09284931 (ISSN) ; Hashemi, E ; Akhavan, O ; Shamsara, M ; Hashemi, M ; Farmany, A ; Daliri Joupari, M ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Recent studies showed that a large amount of graphene oxide accumulated in kidney and liver when it injected intravenously. Evaluation of lethal and apoptosis gene expression in these tissues, which are under stress is very important. In this paper the in vivo dose-dependent effects of graphene oxide and reduced graphene oxide nanoplatelets on kidney and liver of mice were studied. Balb/C mice were treated by 20 mg/kg body weight of nanoplatelets. Molecular biology analysis showed that graphene nanoplatelets injected intravenously lead to overexpression of BAX gene in both kidney and liver tissues (P ≥ 0.01). In addition these nanoparticles significantly increase BCL2 gene expression in both...
Microstructure, morphology and electrochemical properties of Co nanoflake water oxidation electrocatalyst at micro- and nanoscale
, Article RSC Advances ; Volume 7, Issue 21 , 2017 , Pages 12923-12930 ; 20462069 (ISSN) ; Solaymani, S ; Ghaderi, A ; Bramowicz, M ; Kulesza, S ; Ţălu, Ş ; Pourreza, M ; Ghasemi, S ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
Nowadays, fossil fuel limitations and environmental concerns push researchers to find clean and renewable energy resources. Solar hydrogen production via water splitting reactions in electrochemical and/or photo-electrochemical systems has been accepted as a promising route and efficient electrocatalysts are involved in both. Here, cobalt nanoflakes with an oxide/hydroxide surface and a conductive metallic core are grown on commercially available steel mesh modified with carbon based nanocomposites as a support layer. The portion of reduced graphene oxide sheets was changed from 0 to 100 wt% and the correlation of this concentration with the surface morphology and electro-catalytic activity...
High-Performance fiber-shaped flexible asymmetric microsupercapacitor based on ni(oh)2 nanoparticles-decorated porous dendritic ni-cu film/cu wire and reduced graphene oxide/carbon fiber electrodes
, Article ACS Sustainable Chemistry and Engineering ; Volume 6, Issue 11 , 2018 , Pages 14574-14588 ; 21680485 (ISSN) ; Naderi, L ; Mohammadi, R ; Sharif University of Technology
American Chemical Society
2018
Abstract
Miniaturization of electronic devices with portable, flexible and wearable characteristics created a great demand for high-performance microscale energy storage devices with lightweight and flexible properties. Among the energy storage devices, wire-shaped supercapacitors (WSSCs) have recently received tremendous attention due to their tiny volume, wearability, high flexibility and potential applications in the next-generation portable/wearable electronic devices. Herein, we successfully fabricated a porous dendritic Ni-Cu film on Cu wire substrate (CWE) for fabrication of high-performance wire-type supercapacitors. The porous structure with dendritic morphology provides a high surface area,...