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molavi--hossein
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Properties Enhancement of Styrene-butadiene-rubber (SBR) by Incorporating Hybrid Nanoparticles based on Metal-Organic Framework (MOF)/Carbon Nanoparticle
, M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
Flexible polymers (elastomers) are especially suitable for dynamic applications, and carbon based fillers are well-known filler for elastomers. These types of fillers are widely used in elastomer matrices for various commercial applications. Some of carbon nano fillers like Nanodiamond cannot (ND) impart such high degree of reinforcement to polymer matrices mainly because of improper filler dispersion and lack of strong filler-polymer interaction.In this effort, we examine the effects of nanodiamond/UiO-66 hybrid nanostructured materials when they are incorporated in styrene-butadiene rubber (SBR) in terms of mechanical, thermal and electrical properties of the nanocomposites.Different...
Preparation and Characterization of Anticorrosive Epoxy Coating based on Inhibitor Loaded Metal-Organic Framework Nanostructures
, M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
In this study, metal-organic frameworks (MOFs) UiO-66 and NH2-UiO-66 were prepared and loaded with 2-mercaptobenzothiazole as corrosion inhibitor .Epoxy coatings containing inhibitor loaded nanoparticles were applied on mild steel to corrosion protection in 3.5 wt.% NaCl solution. Fourier transform infrared spectroscopy (FTIR) was used to confirm Inhibitor loading. In order to estimate the loading amount of corrosion inhibitor, thermogravimetric analysis was investigated. FE-SEM images demonstrated nanoparticle dispersibility in epoxy matrix.The results of electrochemical impedance spectroscopy (EIS) alalysis showed improvement of the corrosion resistance of the coatings containing...
Improvement of Physical and Mechanical Properties of Poly (Ethylene Terephthalate) (PET) by Incorporating Metal-organic Framework (MOF) Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
Over the past decade, MOFs have been extensively studied due to their very high specific surface area and porous structure. Among a wide range of MOFs, UiO-66 has produced widespread attention for its excellent solvent resistance and high thermal stability. This nanoparticle is formed by 12 coordinates between Zr6O4(OH)4 unit and terephthalic acid ligand, and it seems that the similarity of its organic ligand with one of the PET-forming monomers makes them highly compatible. In this study, for the first time, the role of UiO-66 nanoparticles in improving the amount and rate of crystallization and mechanical and rheological properties of PET was investigated using the melt mixing method. For...
Preparation and Characterization of Metal-Organic Framework/Chitosan Nanocomposites to Dye Removal from Aqueous Media
, M.Sc. Thesis Sharif University of Technology ; Shojaei Segherloo, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
The amino groups present in the chemical structure of chitosan have made this material a prominent dye absorbents. But researchers have always taken steps to improve conditions and increase absorption. One of the materials that has attracted most researchers today is metal-organic frameworks. These porous materials with high surface area, optimum thermal resistance and adsorbent dye functional groups have been used as the reinfocing in the chitosan polymer field to adsorb anionic dye (methyl orange) from the aqueous media. One of metal-organic frameworks is UiO-66, which was selected as a reinforcing phase in the polymer field, due to its good stability in aqueous solutions, good thermal...
Synthesis and Investigation of Hybrid Nanoparticles Based on Metal-Organic Framework on the Properties of Polymeric Coatings
, M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor) ; Nematollahzadeh, Ali (Co-Supervisor)
Abstract
In this study, MOF / PAN hybrid nanoparticles have been used as active anti-corrosion inhibitors for the first time. At first, UIO-66, PANI, and hybrid nanoparticles were synthesized based on different weight percentages of UIO-66. Their functional groups, crystal structure, nanoparticle morphology, porosity structure, stability and thermal performance were investigated using FT-IR, XRD, FE-SEM, BET, and TGA analyses, respectively. The type of nanoparticle structure formation was investigated by TEM images. The particle size distribution along with their surface charge was determined using DLS analysis. Inhibitory properties of nanoparticles were evaluated by TOEFL polarization method and...
Synthesis and Characterization of Chitosan-Modified Metal-Organic Framework to Remove Contaminants from Aquatic Environment
, M.Sc. Thesis Sharif University of Technology ; Hamzehluyan, Tayebeh (Supervisor) ; Shojaei Segherloo, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
In the present work, a series of nanohybrids based on ZIF-8 as a physicochemical stable metal-organic framework (MOF) and different amounts of Chitosan (CS) (0.5–15 wt%) were synthesized and used as adsorbents for anionic (Congo Red, CR) and cationic (malachite green, MG) dyes from contaminated water in single and binary dye solutions. The single adsorbents and their nanohybrids were characterized by FESEM, FTIR, XRD, TGA, BET, and zeta potential measurements. The experimental adsorption results displayed that the synthesized nanohybrids presented higher adsorption capacity for anionic dyes compared to cationic dyes in both single and binary dye solutions. It was deduced that the...
Fabrication and Modification of Nano-Filtration Membrane for Effective Removal of Pharmaceutical Pollutants from Water
, M.Sc. Thesis Sharif University of Technology ; Musavi Soghondikolaei, Abbas (Supervisor) ; Bastani, Dariush (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
In this research, the separation of tetracycline (TC) as a pharmaceutical pollutant from water using a nanofiltration membrane process was investigated. For this purpose, a set of polymer-based nanofiltration membranes containing various amounts of the metal-organic framework (MOF-808) which are stable in water, were prepared via the phase inversion method. Due to the hydrophobic nature of the polysulfone and its tendency to fouling in the membrane filtration process, MOF-808 particles were used as agents to enhance the hydrophilicity of the membrane surfaces. In order to achieve this goal, MOF-808 was synthesized via solvothermal method and activated using two different methods:...
Mixed-matrix composite membranes based on uio-66-derived MOFs for CO 2 separation
, Article ACS Applied Materials and Interfaces ; Volume 11, Issue 9 , 2019 , Pages 9448-9461 ; 19448244 (ISSN) ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
We demonstrated a novel mixed-matrix composite membrane (MMCM) based on acrylated polyurethane (APU) and UiO-66 nanoparticles to separate CO 2 /N 2 mixture. UiO-66 and functionalized UiO-66 including NH 2 -UiO-66 and glycidyl methacrylate (GMA)-UiO-66 were loaded into APU/2-hydroxyethyl methacrylate (APUH) matrix at variable concentrations between 3 and 30 wt %. APUH/GMA-UiO-66 MMCMs exhibited strong adhesion with a support layer of polyester/polysulfone, which was not deteriorated after immersion in water for a long time (20 days). Incorporation of UiO-66 and its functionalized forms increased simultaneously permeability and CO 2 /N 2 selectivity, which were indeed superior in comparison...
Design and Improvement of Meta-Surface Based MIMO Antennas for 5G Millimeter Wave
, M.Sc. Thesis Sharif University of Technology ; Akbari, Mahmood (Supervisor)
Abstract
Wireless communication systems play a pivotal role in the daily lives of individuals. Given the escalating demand for higher data rates and enhanced reliability, there is an imperative need for cutting-edge communication technologies. Rigorous research is being conducted in these systems to refine and optimize antenna structures, aiming at augmenting performance, escalating data transmission rates, and mitigating interference. Microstrip antenna structures have garnered considerable attention due to their diminutive dimensions, adaptability to planar and non-planar surfaces, simplistic design, cost-effectiveness, and mechanical resilience. These antennas, featuring diverse patch shapes,...
Experimental study on the influence of initial pH, ionic strength, and temperature on the selective adsorption of dyes onto nanodiamonds
, Article Journal of Chemical and Engineering Data ; Volume 64, Issue 4 , 2019 , Pages 1508-1514 ; 00219568 (ISSN) ; https://pubs.acs.org/doi/abs/10.1021/acs.jced.8b01091 ; Pourghaderi, A ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the...
Experimental study on the influence of initial pH, Ionic strength, and temperature on the selective adsorption of dyes onto nanodiamonds
, Article Journal of Chemical and Engineering Data ; 2019 ; 00219568 (ISSN) ; Pourghaderi, A ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the...
Rapid and tunable selective adsorption of dyes using thermally oxidized nanodiamond
, Article Journal of Colloid and Interface Science ; Volume 524 , 2018 , Pages 52-64 ; 00219797 (ISSN) ; Shojaei, A ; Pourghaderi, A ; Sharif University of Technology
2018
Abstract
In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange, MO) and cationic (methylene blue, MB) dyes from aqueous solution was investigated. Employing fourier transform infrared (FTIR) spectroscopy, Boehm titration method and zeta potential, it was found that the simple thermal oxidation of ND at 425 °C, increased the content of carboxylic acid of ND and accordingly the zeta potential of ND decreased considerably. Therefore, a series of oxidized NDs (OND) at various oxidation times and as-received untreated ND (UND) was used as adsorbents of MO and MB. The adsorption experiments exhibited that UND had large adsorption capacity, very fast adsorption...
Experimental study on the influence of initial pH, ionic strength, and temperature on the selective adsorption of dyes onto nanodiamonds
, Article Journal of Chemical and Engineering Data ; 2019 ; 00219568 (ISSN) ; Pourghaderi, A ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the...
Superior fatigue and mechanical properties of ethylene-propylene diene monomer rubber incorporated with Zr-based metal–organic framework
, Article Journal of Polymer Research ; Volume 30, Issue 1 , 2023 ; 10229760 (ISSN) ; Shojaei, A ; Molavi, H ; Sharif University of Technology
Springer Science and Business Media B.V
2023
Abstract
This research reports the remarkable effects of Zr-based metal–organic framework, i.e. UiO-66, on cross-linked network structure and mechanical behaviors of ethylene-propylene diene monomer (EPDM) rubber under sulfur vulcanization systems. To this end, EPDM rubber was vulcanized with conventional (CV), semi-efficient (SEV) and efficient (EV) vulcanization systems. In addition, EPDM nanocomposites containing 5 phr UiO-66 with all three vulcanization systems were also prepared, for the sake of comparison with their corresponding unfilled samples. While the unfilled EPDM vulcanizates showed expectable behaviors in cross-linking density estimated by swelling experiment and cure-rheometer...
Ethylenediamine grafting to functionalized NH2-UiO-66 using green aza-Michael addition reaction to improve CO2/CH4 adsorption selectivity
, Article Industrial and Engineering Chemistry Research ; Volume 57, Issue 20 , April , 2018 , Pages 7030-7039 ; 08885885 (ISSN) ; Ahmadi Joukani, F ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2018
Abstract
Three versions of zirconium-based metal organic frameworks, NH2-UiO-66, GMA-UiO-66, and EDA-UiO-66, were synthesized and employed as adsorbent for CO2/CH4 separation. GMA-UiO-66 was synthesized via a ring opening reaction between the amine species in the framework and epoxy groups in glycidyl methacrylate (GMA), while the green aza-Michael addition reaction was used for the first time to functionalize GMA-UiO-66 with ethylenediamine (EDA). The products were characterized by BET, XRD, TGA, FESEM, ICP-OES, 1H NMR, mass spectroscopy, and FTIR-ATR methods to monitor their textural properties before and after functionalization. The results indicated that GMA was successfully grafted to the...
Improving mixed-matrix membrane performance: Via PMMA grafting from functionalized NH2-UiO-66
, Article Journal of Materials Chemistry A ; Volume 6, Issue 6 , 2018 , Pages 2775-2791 ; 20507488 (ISSN) ; Shojaei, A ; Mousavi, S. A ; Sharif University of Technology
Royal Society of Chemistry
2018
Abstract
The major obstacles in gas separation by mixed-matrix membranes (MMMs) are poor dispersion and poor affinity between polymers and fillers. The present study demonstrates that these challenges can be overcome appropriately by utilizing a series of synthesized stand-alone MMMs. The matrix used was polymethyl methacrylate (PMMA) and the MMMs were synthesized by in situ polymerization of methyl methacrylate (MMA) in the presence of UiO-66, NH2-UiO-66 and vinyl group attached UiO-66. In situ polymerization of MMA in the presence of vinyl attached UiO-66 resulted in PMMA grafted UiO-66 with a high degree of grafting. Microscopic analysis by field emission scanning electron microscopy (FESEM)...
Photo-curable acrylate polyurethane as efficient composite membrane for CO2 separation
, Article Polymer ; Volume 149 , 2018 , Pages 178-191 ; 00323861 (ISSN) ; Shojaei, A ; Mousavi, S. A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The current investigation was to present composite membranes with strong interfacial adhesion between top polymeric selective layer and the bottom micro-porous support layer with appropriate gas permeation behavior and practically suitable processing characteristics. To this end, a series of acrylate-terminated polyurethanes (APUs) based on poly (ethylene glycol) (PEG) with different molecular weights (Mn) of 600, 1000, 1500, 2000 and 4000 g/mol, toluene diisocyanate (TDI), and 2-hydroxyethyl methacrylate (HEMA) were synthesized. Composite membranes were prepared with UV-curable acrylate-terminated polyurethane/acrylate diluent (APUAs) as selective layer and polyester/polysulfone (PS/PSF) as...
Nanodiamond-filled chitosan as an efficient adsorbent for anionic dye removal from aqueous solutions
, Article Journal of Environmental Chemical Engineering ; Volume 6, Issue 2 , 2018 , Pages 3283-3294 ; 22133437 (ISSN) ; Hakimian, A ; Shojaei, A ; Molavi, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
A series of novel chitosan/nanodiamond (CTS/ND) composites containing NDs with variable surface carboxyl groups and various concentrations were prepared using solution casting method. Powdery CTS/ND composites were employed as the adsorbent of a model anionic dye (methyl orange, MO). Experimental results showed that the incorporation of NDs with high carboxylic content (ND-H) in to CTS increased substantially the maximum adsorption capacity of neat CTS from 167 mg/g to 454 mg/g. The remarkable adsorption capacity of dye on CTS/ND composites was associated to the oxygen-containing groups on the outer surface of NDs which would be beneficial to interact with the dye molecules through hydrogen...
Selective dye adsorption by highly water stable metal-organic framework: Long term stability analysis in aqueous media
, Article Applied Surface Science ; Volume 445 , 2018 , Pages 424-436 ; 01694332 (ISSN) ; Hakimian, A ; Shojaei, A ; Raeiszadeh, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A highly water stable metal-organic framework (MOF) based on zirconium, i.e. UiO-66, was synthesized and then employed to adsorptive removal of an anionic dye, methyl orange (MO), and a cationic dye, methylene blue (MB), from aqueous solution. In this work, for the first time, the long term stability of UiO-66 in water was investigated for 12 months. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and N2 adsorption/desorption analysis were employed to monitor the textural alteration of UiO-66 during water aging. The results indicated that the structure of UiO-66 was mostly retained and its adsorption capacity toward dyes exhibited minor loss after long term water...
Ultrafast and simultaneous removal of anionic and cationic dyes by nanodiamond/UiO-66 hybrid nanocomposite
, Article Chemosphere ; Volume 247 , May , 2020 ; Neshastehgar, M ; Shojaei, A ; Ghashghaeinejad, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this research, UiO-66 and its composite nanoparticles with thermally oxidized nanodiamond (OND) were synthesized via a simple solvothermal method and utilized as solid adsorbent for the removal of anionic methyl red (MR) dye and cationic malachite green (MG) dye from contaminated water. The synthesized adsorbents were analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), N2 adsorption–desorption, and zeta potential analyzer. The influences of various factors such as initial concentrations of the dyes, adsorption process time, solution pH, solution temperature and ionic...