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multiwalled-carbon-nanotubes
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The effect of multiwalled carbon nanotubes and activated carbon on the morphology and photocatalytic activity of TiO2/C hybrid materials
, Article Catalysis Science and Technology ; Volume 1, Issue 2 , 2011 , Pages 279-284 ; 20444753 (ISSN) ; Ghasemi, S ; Gholami, M. R ; Sharif University of Technology
2011
Abstract
TiO2 nanoparticles supported on activated carbon (AC) and multiwalled carbon nanotubes (MWCNTs) were prepared by the sol-gel method using ultrasonic irradiation. All the prepared samples were calcined at different temperatures and characterized by X-ray diffraction, nitrogen adsorption/desorption isotherms, scanning electron microscopy, transmission electron microscopy and diffuse reflectance spectroscopy. The effects of size and type of carbon on the morphology and photocatalytic activity of the resulting hybrid materials were investigated. The results showed that a decrease in the size of the carbon led to a decrease in size of TiO2 nanoparticles. Both AC and MWCNTs retarded the...
Nanoparticle catalysts
, Article Journal of Physics D: Applied Physics ; Volume 42, Issue 23 , 2009 ; 00223727 (ISSN) ; Sharif University of Technology
2009
Abstract
In this review, the importance of nanoparticles (NPs), with emphasis on their general and specific properties, especially the high surface-to-volume ratio (A/V), in many technological and industrial applications is studied. Some physical and chemical preparation methods for growing several metallic and binary alloy NP catalysts are reviewed. The growth and mechanism of catalytic reactions for synthesis of 1D nanostructures such as ZnO nanowires and multiwall carbon nanotubes (MWCNTs) are discussed. Gas-phase production with emphasis on dependence of catalytic activity and selectivity on size, shape and structure of NPs is also investigated. Application of NP catalysts in several...
MWCNT/WO3 nanocomposite photoanode for visible light induced water splitting
, Article Journal of Solid State Chemistry ; Volume 204 , 2013 , Pages 341-347 ; 00224596 (ISSN) ; Reyhani, A ; Naseri, N ; Moshfegh, A. Z ; Sharif University of Technology
2013
Abstract
The Multi-walled carbon nanotube (MWCNT)/WO3 nanocomposite thin films with different MWCNT's weight percentages were prepared by sol-gel method as visible light induced photoanode in water splitting reaction. Weight percentage of MWCNT in the all nanocomposite thin films was confirmed by TGA/DSC analysis. According to XPS analysis, oxygenated groups at the surface of the MWCNT and stoichiometric formation of WO3 thin films were determined, while the crystalline structure of the nanocomposite samples was studied by XRD indicating (0 0 2) peak of MWCNT in the monoclinic phase of WO3. The influence of different weight percentage (wt%) of MWCNT on WO3 photoactivity showed that the electron...
Hydro-purification of crude terephthalic acid using palladium catalyst supported on multi-wall carbon nanotubes
, Article Journal of Industrial and Engineering Chemistry ; 2015 ; ISSN: 1226086X ; Khorasheh, F ; Rashidi, A. M ; Safekordi, A. A ; Sharif University of Technology
Abstract
Palladium catalysts supported on functionalized multi-wall carbon nanotubes were synthesized for hydro-purification of crude terephthalic acid containing 2100ppm 4-carboxybenzaldehyde (4-CBA) as impurity. PdCl2 and Pd(OAc)2 were used as precursors. Palladium loadings were 0.05 to 0.6wt.% with catalysts reduced at 200 to 400°C. Catalysts prepared from both precursors with least 0.3wt.% palladium resulted in 99%+ removal of 4-CBA. The most desired selectivity was obtained for the catalyst with PdCl2 as precursor, reduction temperature of 300°C, and palladium loading of 0.3wt.%. This catalyst had slightly better performance than the commercial catalyst (0.5wt.% of palladium on activated carbon)...
Synthesis of Reduced Graphene Oxide-Carbon Nanotubes (rGO-CNT) Composite and Its Use As a Novel Catalyst Support for Hydro-Purification of Crude Terephthalic Acid
, Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 31 , 2015 , Pages 7591-7603 ; 08885885 (ISSN) ; Rashidi, A. M ; Safekordi, A. A ; Aghabozorg, H. R ; Khorasheh, F ; Sharif University of Technology
American Chemical Society
2015
Abstract
Palladium nanocatalysts supported on reduced graphene oxide (rGO), multi walled carbon nanotubes (MWCNT), and rGO/CNT composite were synthesized by a wet impregnation method using PdCl2 as a precursor. Palladium loading was 0.3 wt %, and the catalysts were reduced at 300°C. The catalysts were characterized by inductively coupled plasma, Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared spectroscopy, X-ray powder diffraction, transmission electron microscopy, temperatue-programmed reduction, temperatue-programmed desorption, and Raman spectroscopy. The performance of the catalysts was investigated for hydro-purification of crude terephthalic acid (CTA) containing...
Hydro-purification of crude terephthalic acid using palladium catalyst supported on multi-wall carbon nanotubes
, Article Journal of Industrial and Engineering Chemistry ; Volume 28 , August , 2015 , Pages 202-210 ; 1226086X (ISSN) ; Khorasheh, F ; Rashidi, A. M ; Safekordi, A. A ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2015
Abstract
Palladium catalysts supported on functionalized multi-wall carbon nanotubes were synthesized for hydro-purification of crude terephthalic acid containing 2100ppm 4-carboxybenzaldehyde (4-CBA) as impurity. PdCl2 and Pd(OAc)2 were used as precursors. Palladium loadings were 0.05 to 0.6wt.% with catalysts reduced at 200 to 400°C. Catalysts prepared from both precursors with least 0.3wt.% palladium resulted in 99%+ removal of 4-CBA. The most desired selectivity was obtained for the catalyst with PdCl2 as precursor, reduction temperature of 300°C, and palladium loading of 0.3wt.%. This catalyst had slightly better performance than the commercial catalyst (0.5wt.%...
Hydrogenation of crude terephthalic acid by supported Pd and Pd-Sn catalysts on functionalized multiwall carbon nanotubes
, Article Chemical Engineering Research and Design ; Volume 109 , 2016 , Pages 41-52 ; 02638762 (ISSN) ; Safekordi, A. A ; Rashidzadeh, M ; Rashidi, A. M ; Khorasheh, F ; Sharif University of Technology
Institution of Chemical Engineers
2016
Abstract
Liquid phase hydro-purification of crude terephthalic acid (CTA) was performed using supported Pd and Pd-Sn catalysts on functionalized multi-wall carbon nanotubes (FMWCNT). Pd/FMWCNT catalysts were prepared by wet impregnation with Pd loadings of 0.05 to 0.6 wt.%. Pd-Sn/FMWCNT catalysts were prepared by co-impregnation (CI) and successive impregnation (SI) using 0.3 wt.% Pd loading and Sn/Pd molar ratios of 0.1 and 0.35 for the CI method and 0.05 to 0.35 for the SI method. Pd loading of 0.3 wt.% for Pd/FMWCNT was sufficient to decrease the 4-carboxybenzaldehyde (4-CBA) content of CTA from 2100 ppm to 5.5 ppm without excessive hydrogenation of terephthalic acid (TA). The commercial catalyst...
Horseradish peroxidase immobilization on amine functionalized carbon nanotubes: Direct electrochemistry and bioelectrocatalysis
, Article Progress in Reaction Kinetics and Mechanism ; Volume 37, Issue 2 , May , 2012 , Pages 161-172 ; 14686783 (ISSN) ; Ghourchian, H ; Gholami, M. R ; Rafiee Pour, H. A ; Sharif University of Technology
2012
Abstract
Horseradish peroxidase (HRP) was successfully immobilized on amine functionalized TiO 2-coated multiwalled carbon nanotubes (NH 2-TiO 2-CNTs) by a convenient and efficient method. Electrochemical impedance spectroscopy, cyclic voltammetry and amperometry were applied to characterize the HRP/NH 2-TiO 2-CNT nano-composite. These techniques showed that the NH 2-TiO 2-CNTs greatly enhance the electron transfer between HRP and the modified electrode. Owing to the redox reaction of the electroactive centre of HRP, the HRP/NH 2-TiO 2-CNTs modified electrode exhibited a pair of quasi-reversible peaks with a peak-to-peak separation (ΔE p) of 70.6mV and a formal potential (E 0′) of -367.65mV (versus...
Enhancing the photocatalytic performance of Ag3PO4 by incorporating g-C3N4 and MWCNTs: Optimisation of removal of Acid Blue 92
, Article Progress in Reaction Kinetics and Mechanism ; Volume 41, Issue 3 , 2016 , Pages 277-288 ; 14686783 (ISSN) ; Armandsefat, F ; Mohaghegh, N ; Ahmadinasab, N ; Sharif University of Technology
Science Reviews 2000 Ltd
2016
Abstract
The main aim of the present study was to enhance the degradation capacity of Acid Blue 92 (AB92) by visible-light-active Ag3PO4 nanocomposites based on g-C3N4 and Multiwalled Carbon Nanotubes (MWCNTs). The nanocomposites were fabricated through a tunable in situ deposition method. The properties of the resulting samples were investigated by X-ray diffraction, scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. The photocatalytic activity results revealed that the Ag3PO4/g-C3N4 heterojunction inorganic/organic composite exhibited an improvement in both efficiency and the rate of AB92 photodegradation in comparison with the others. The enhanced photocatalytic...
Fabrication of porous polyphosphate carbon composite on nickel foam as an efficient binder-less electrode for symmetric capacitive deionization
, Article Separation and Purification Technology ; Volume 276 , 2021 ; 13835866 (ISSN) ; Mahdi Ahadian, M ; Shahrokhian, S ; Amini, M. K ; Sharif University of Technology
Elsevier B.V
2021
Abstract
An efficient and commercially available method is introduced for preparation of a binder-free electrode for capacitive deionization (CDI) application. An interconnected porous composite consisting of polyphosphate (PPO), graphene (Gr) and multi-walled carbon nanotube (CNT) is fabricated and assembled on a Ni foam substrate to prepare a binder-free electrode (Ni/PPOGrCNT). The resulting electrodes were characterized using various instrumental techniques such as TEM, SEM, EDS, XRD, FT-IR, Raman, XPS and XRF. Characterization results indicated that a mesoporous PPO structure is formed on a 3D assembly of carbon backbone. Accordingly, the 3-D porous structure facilitates the ion diffusion into...
An investigation on the structural characteristics and reinforcement of melt processed polyamide 66/multiwalled carbon nanotube composites
, Article Polymers for Advanced Technologies ; Vol. 25, issue. 4 , 2014 , pp. 406-417 ; ISSN: 10427147 ; Nourbakhsh, P ; Faghihi, M ; Sharif University of Technology
Abstract
Properties of melt processed polyamide 66 (PA66)/multiwalled carbon nanotube composite were first characterized experimentally. The experimental results exhibited the formation of crystalline layer around the nanotubes and a considerable enhancement in mechanical properties by incorporation of multiwalled carbon nanotube up to 1 wt%. Mechanical properties were analyzed in terms of structural parameters using micromechanical models proposed in this study. It was suggested that the mechanical properties were greatly dominated by crystalline layer and nanotube length. It was also deduced that the melt mixing process caused a significant nanotube breakage restricting further enhancement of...
Effect of Fe3 concentration on MWCNTs formation in liquid arcing method
, Article Physica B: Condensed Matter ; Volume 405, Issue 20 , October , 2010 , Pages 4344-4349 ; 09214526 (ISSN) ; Gheytani, S ; Simchi, A ; Sharif University of Technology
2010
Abstract
The formation of multi-walled carbon nanotubes (MWCNTs) during arc discharge in aqueous solutions of Fe2(SO4)3 and FeCl3 was studied. The concentration of iron ions changed from zero (deionized water) to 0.25 M and the cathodic products were examined by transmission electron microscopy, Raman spectrometry, and thermal gravimetric analysis. The experimental results showed that the crystallinity of MWCNTs is improved by increasing the concentration of iron ions. Nevertheless, the process yield and overall quality of the produced CNTs were significantly affected by iron concentration in the aqueous solution. This observation suggested that there should be an optimum iron concentration at which...
Thermal degradation behavior and kinetic analysis of ultra high molecular weight polyethylene based multi-walled carbon nanotube nanocomposites prepared via in-situ polymerization
, Article Journal of Macromolecular Science, Part A: Pure and Applied Chemistry ; Volume 49, Issue 9 , 2012 , Pages 749-757 ; 10601325 (ISSN) ; Saadatabadi, A. R ; Khorasheh, F ; Sharif University of Technology
T&F
2012
Abstract
Thermal degradation behavior of multi-wall carbon nanotubes (MWCNTs)/ultra high molecular weight polyethylene (UHMWPE) nanocomposites, with different nanotubes contents (0.5, 1.5 and 3.5 wt%) prepared via in-situ polymerization technique have been investigated using thermal gravimetric analysis (TGA). TGA spectra revealed that these nanocomposites had enhanced thermal stability and no significant mass loss (<0.4 wt%) occurred up to 350°C. Thermal degradation of these UHMWPE/MWCNT nanocomposites was investigated in terms of parameters such as the onset temperature of degradation (T 10), the decomposition temperature at 50% wt loss (T 50), the degradation temperature of maximum rate of the...
Pd-Au nanoparticle decorated carbon nanotube as a sensing layer on the surface of glassy carbon electrode for electrochemical determination of ceftazidime
, Article Materials Science and Engineering C ; Vol. 34, issue. 1 , 2014 , pp. 318-325 ; ISSN: 09284931 ; Salimian, R ; Rastgar, S ; Sharif University of Technology
Abstract
A simple electrodeposition method is employed to construct a thin film modifier of palladium-gold nanoparticles (Pd-AuNPs) decorated multi-walled carbon nanotube (MWCNT) on the surface of glassy carbon electrode (GCE). Morphology and property of Pd-AuNPs-MWCNT have been examined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Electrochemical performance of Pd-AuNPs-MWCNT/GCE for detection of ceftazidime (CFZ) has been investigated by cyclic voltammetry (CV). This nanostructured film modified electrode effectively exhibited enhanced properties for detection of ceftazidime (CFZ). The effects of various experimental variables such as, the amount of casted MWCNT,...
Fabrication of an electrochemical sensor based on the electrodeposition of Pt nanoparticles on multiwalled carbon nanotubes film for voltammetric determination of ceftriaxone in the presence of lidocaine, assisted by factorial-based response-surface methodology
, Article Journal of Solid State Electrochemistry ; Vol. 18, issue. 1 , 2014 , p. 77-88 ; Hosseini-Nassab, N ; Kamalzadeh, Z ; Sharif University of Technology
Abstract
A glassy carbon electrode (GCE) is modified with platinum nanoparticle (PtNPs) decorated multiwalled carbon nanotube (MWCNT). The modified electrode is applied for the determination of ceftriaxone (CFX) in the presence of lidocaine. Different methods were used to characterize the surface morphology of the modified electrode. The electrochemical behavior of CFX was investigated at GCE, MWCNT/GCE and PtNPs/MWCNT/GCE. A factorial-based response-surface methodology was used to find out the optimum conditions with minimum number of experiments. Under the optimized conditions, oxidation peak currents increased linearly with CFX concentration in the range of 0.01-10.00 μM with a detection limit of...
Electrochemical determination of clozapine on MWCNTs/new coccine doped ppy modified GCE: An experimental design approach
, Article Bioelectrochemistry ; Volume 90 , 2013 , Pages 36-43 ; 15675394 (ISSN) ; Kamalzadeh, Z ; Hamzehloei, A ; Sharif University of Technology
2013
Abstract
The electrooxidation of clozapine (CLZ) was studied on the surface of a glassy carbon electrode (GCE) modified with a thin film of multiwalled carbon nanotubes (MWCNTs)/new coccine (NC) doped polypyrrole (PPY) by using linear sweep voltammetry (LSV). The pH of the supporting electrolyte (D), drop size of the cast MWCNTs suspension (E) and accumulation time of CLZ on the surface of modified electrode (F) was considered as effective experimental factors and the oxidation peak current of CLZ was selected as the response. By using factorial-based response-surface methodology, the optimum values of factors were obtained as 5.44, 10 μL and 300 s for D, E and F respectively. Under the optimized...
Electrochemical deposition of gold nanoparticles on carbon nanotube coated glassy carbon electrode for the improved sensing of tinidazole
, Article Electrochimica Acta ; Volume 78 , September , 2012 , Pages 422-429 ; 00134686 (ISSN) ; Rastgar, S ; Sharif University of Technology
2012
Abstract
The electrochemical reduction of tinidazole (TNZ) is studied on gold-nanoparticle/carbon-nanotubes (AuNP/CNT) modified glassy carbon electrodes using the linear sweep voltammetry. An electrochemical procedure was used for the deposition of gold nanoparticles onto the carbon nanotube film pre-cast on a glassy carbon electrode surface. The resulting nanoparticles were characterized by scanning electron microscopy and cyclic voltammetry. The effect of the electrodeposition conditions, e.g., salt concentration and deposition time on the response of the electrode was studied. Also, the effect of experimental parameters, e.g., potential and time of accumulation, pH of the buffered solutions and...
Fabrication of a modified electrode based on Fe3 O4 NPs/MWCNT nanocomposite: Application to simultaneous determination of guanine and adenine in DNA
, Article Bioelectrochemistry ; Volume 86 , 2012 , Pages 78-86 ; 15675394 (ISSN) ; Rastgar, S ; Amini, M. K ; Adeli, M ; Sharif University of Technology
Abstract
Multi-walled carbon nanotubes decorated with Fe 3O 4 nanoparticles (Fe 3O 4NPs/MWCNT) were prepared and used to construct a novel biosensor for the simultaneous detection of adenine and guanine. The direct electro-oxidation of adenine and guanine on the modified electrode were investigated by linear sweep voltammetry. The results indicate a remarkable increase in the oxidation peak currents together with negative shift in the oxidation peak potentials for both adenine and guanine, in comparison to the bare glassy carbon electrode (GCE). The surface morphology and nature of the composite film deposited on GCE were characterized by transmission electron microscopy, atomic force microscopy,...
Electrochemical determinations of 6-mercaptopurine on the surface of a carbon nanotube-paste electrode modified with a cobalt salophen complex
, Article Journal of Solid State Electrochemistry ; Volume 16, Issue 4 , April , 2012 , Pages 1643-1650 ; 14328488 (ISSN) ; Ghorbani Bidkorbeh, F ; Mohammadi, A ; Dinarvand, R ; Sharif University of Technology
2012
Abstract
A mixture of multi-walled carbon nanotube/graphite paste electrode modified with a salophen complex of cobalt was prepared and was applied for the study of the electrochemical behavior of 6-mercaptopurine (MP) using cyclic and differential pulse voltammetry (DPV). An excellent electrocatalytic activity toward the oxidation of MP was achieved, which led to a considerable lowering in the anodic overpotential and remarkable increase in the response sensitivity in comparison with unmodified electrode. Utilizing DPV method, a linear dynamic range of 1-100 μM with detection limit of 0.1 μM was obtained in phosphate buffer of pH 3.0. The electrochemical detection system was very stable, and the...
Gold electrode modified with self-assembled monolayer of cysteamine-functionalized mwcnt and its application in simultaneous determination of dopamine and uric acid
, Article Electroanalysis ; Volume 24, Issue 2 , February , 2012 , Pages 425-432 ; 10400397 (ISSN) ; Mahdavi Shakib, A ; Ghalkhani, M ; Saberi, R. S ; Sharif University of Technology
Abstract
The voltammetric behavior of dopamine (DA) and uric acid (UA) on a gold electrode modified with self-assembled monolayer (SAM) of cysteamine (CA) conjugated with functionalized multiwalled carbon nanotubes (MWCNTs) was investigated. The film modifier of functionalized SAM was characterized by means of scanning electron microscopy (SEM) and also, electrochemical impedance spectroscopy (EIS) using para-hydroquinone (PHQ) as a redox probe. For the binary mixture of DA and UA, the voltammetric signals of these two compounds can be well separated from each other, allowing simultaneous determination of DA and UA. The effect of various experimental parameters on the voltammetric responses of DA and...