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Stable dye-sensitized solar cells based on a gel electrolyte with ethyl cellulose as the gelator
, Article Applied Physics A: Materials Science and Processing ; Volume 120, Issue 3 , September , 2015 , Pages 869-874 ; 09478396 (ISSN) ; Tajabadi, F ; Jabbari, A ; Taghavinia, N ; Sharif University of Technology
Springer Verlag
2015
Abstract
A simple gelating process is developed for the conventional acetonitrile-based electrolyte of dye solar cells, based on ethyl cellulose as the gelator. The electrolyte becomes quasi-solid-state upon addition of an ethanolic solution of ethyl cellulose to the conventional acetonitrile-based liquid electrolyte. The photovoltaic conversion efficiency with the new gel electrolyte is only slightly lower than with the liquid electrolyte, e.g., 6.5 % for liquid electrolyte versus 5.9 % for gel electrolyte with 5.8 wt% added ethyl cellulose. Electrolyte gelation has small effect on the ionic diffusion coefficient of iodide, and the devices are remarkably stable for at least 550 h under irradiation...
Synthesis of magnetic graphene oxide-containing nanocomposite hydrogels for adsorption of crystal violet from aqueous solution
, Article RSC Advances ; Volume 5, Issue 41 , Mar , 2015 , Pages 32263-32271 ; 20462069 (ISSN) ; Nazari, M ; Hosseini, S. H ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Magnetic nanocomposite hydrogels containing different amounts of graphene oxide were synthesized and characterized by FTIR, XRD, TGA, SEM, TEM, VSM and UV-vis spectroscopy. The prepared hydrogels were used as adsorbents for removal of a cationic dye, crystal violet, from water. The kinetics and isotherm of adsorption and the effect of different experimental conditions such as graphene oxide content, pH of the solution, contact time, adsorbent dosage and initial dye concentration on adsorption capacity were then investigated. Parameters related to kinetics and isotherm models were calculated and discussed. It was found that adsorption is well-described by pseudo-second-order kinetics and...
Electrodeposited multi-walled carbon nanotubes on Ag-loaded TiO2 nanotubes/Ti plates as a new photocatalyst for dye degradation
, Article RSC Advances ; Volume 5, Issue 56 , 2015 , Pages 44840-44846 ; 20462069 (ISSN) ; Faraji, M ; Gobal, F ; Gholami, M. R ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
MWCNTs/Ag/TiO2NTs plates were synthesized via electrochemical reduction of functionalized multiwalled carbon nanotubes (MWCNTs) on Ag/TiO2NTs. The loading of silver nanoparticles was carried out by electroless reduction of Ag1+ onto TiO2 nanotubes previously formed by anodizing titanium. The SEM analysis revealed that MWCNTs were loaded significantly on the as-prepared Ag/TiO2NTs, where nanoparticles of Ag had grown on the walls of TiO2NTs. The photocatalytic activity of the synthesized plates was evaluated by the photodegradation of Methyl Orange (MO) dye under UV light irradiation. The results indicated that the MWCNTs/Ag/TiO2NTs demonstrated improved efficiency for MO photodegradation in...
Effect of electron irradiation on dye and printability of polypropylene (PP) fabrics: A novel method for decoration of PP fabrics
, Article Journal of the Textile Institute ; Volume 101, Issue 11 , Sep , 2010 , Pages 988-995 ; 00405000 (ISSN) ; Shahidi, S ; Ghoranneviss, M ; Wiener, J ; Anvari, A ; Sharif University of Technology
2010
Abstract
Polypropylene (PP) has a very low value of the surface free energy (approximately 20-25 mJ m-2). And thus, has very weak hydrophilic properties and doesn't have any affinity to any dyestuffs, such as cationic or anionic dyes. In this study, we covered some parts of PP fabrics by mask, and then irradiated them by electrons with different energies. After electron irradiation, the samples were dyed by cationic dyestuff. The result showed that, electron irradiated parts could be dyed easily and the fabric could be printed and decorated simply. The treated surfaces were investigated by scanning electron microscope (SEM), reflective spectrophotometery, and Fourier transform infrared spectroscopy...
Photonic design of embedded dielectric scatterers for dye sensitized solar cells
, Article RSC Advances ; Volume 5, Issue 42 , Mar , 2015 , Pages 33098-33104 ; 20462069 (ISSN) ; Dabirian, A ; Nemati Kharat, A ; Taghavinia, N ; Sharif University of Technology
Abstract
Embedded dielectric scatterers comprise an important approach for light trapping in dye-sensitized solar cells (DSCs) due to their simple fabrication process. The challenge in applying these scatterers lies in finding the optimal dimensions and concentration of the scatterers. This requires many experiments and it is often quite difficult to have a starting point for optimizing the concentration. Based on theories of light propagation in random media, we propose a simple model for DSCs with embedded silica spherical particles. Then, by full-wave optical calculations, we determine a narrow range for the concentration of silica particles that leads to the largest optical absorption in the...
Co–N doped reduced graphene oxide used as efficient electrocatalyst for dye-sensitized solar cells
, Article Solar Energy Materials and Solar Cells ; Volume 157 , 2016 , Pages 591-598 ; 09270248 (ISSN) ; Ploumistos, A ; Sygellou, L ; Nouri, E ; Tasis, D ; Lianos, P ; Sharif University of Technology
Elsevier
Abstract
An efficient electrocatalyst for Pt-free I−/I3 − reduction has been synthesized by high temperature treatment of graphene oxide-cobalt phthalocyanine mixtures. The graphitic material was characterized by various techniques and was found to consist of reduced graphene oxide carrying CoN3 entities, obtained by thermal decomposition of cobalt phthalocyanine. This material had an ionization potential equal to 4.9±0.1 eV and thus it was judged appropriate to act as reduction electrocatalyst for the I−/I3 − redox electrolyte. It was subsequently deposited as thin film on FTO electrodes, which were employed as counter electrodes for dye-sensitized solar cells. Its capacity to reduce I−/I3 − redox...
The effect of pulsewidth of pumping pulse on the stability of distributed feedback dye laser
, Article Laser Physics ; Volume 27, Issue 4 , 2017 ; 1054660X (ISSN) ; Rahbari, M ; Sadighi Bonabi, R ; Sharif University of Technology
Institute of Physics Publishing
2017
Abstract
The generation of a single and stable picosecond pulse by distributed feedback dye laser is investigated in this work. The numerical result for the rate equation system that includes the thermal effects in the lasing medium is provided. By applying this model to Rhodamine 6G, it is found that considerable improvement in the stability of the laser can be achieved by pumping the system with narrower laser pulses. The simulation shows that if the dye solution is pumped by sub-200 ps pulse, the laser can be operated in single-pulse output mode with acceptable stability in pulsewidth over a long range of pumping intensity. This result is confirmed by a more complicated model composed of...
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...
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...
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...
Decolorization of reactive blue 19 dye from textile wastewater by the UV/H2O2 process
, Article Journal of Applied Sciences ; Volume 8, Issue 6 , 2008 , Pages 1108-1112 ; 18125654 (ISSN) ; Ghaneian, M. T ; Hashemian, S. J ; Moussavi, G ; Khavanin, A ; Ghanizadeh, G ; Sharif University of Technology
Asian Network for Scientific Information
2008
Abstract
Photo-oxidation of dyes is a new concern among researchers since it offers an attractive method for decoloration of dyes and breaks them into simple mineral forms. An advanced oxidation process, UV/H2O2, was investigated in a laboratory scale photoreactor for decolorization of the Reactive blue 19 (RB19 dye from synthetic textile wastewater. The effects of operating parameters such as hydrogen peroxide dosage, pH, initial dye concentration and UV dosage, on decolorization have been evaluated. The RB19 solution was completely decolorized under optimal hydrogen peroxide dosage of 2.5 mmol L-1 and low-pressure mercury UV-C lamps (55 w) in less than 30 min. The decolorization rate followed...
Mechanistic evaluation of cationic dyes adsorption onto low-cost calcinated aerated autoclaved concrete wastes
, Article International Journal of Environmental Science and Technology ; 2021 ; 17351472 (ISSN) ; Eftekhari, M ; Tabrizi, M. G ; Fathollahi Fard, A. M ; Tian, G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Application of construction and demolition (C&D) wastes were considered as sustainable development goals (SDGs) for maintaining raw materials. Also, lightweight concretes such as aerated autoclaved concrete (AAC) were used for partitioning spaces in the building industry. Moreover, the waste products of the mentioned materials were increased due to the rise of old construction demolitions. This study contributes a calcinated aerated autoclaved concrete (CAAC) which is efficient, powerful, highly rapid, non-expensive and novel adsorbent for the removal of cationic dyes including malachite green (MG), methyl violet (MV) and methylene blue (MB) form water samples. The impacts of different...
Facile synthesis of polyaniline@UiO-66 nanohybrids for efficient and rapid adsorption of methyl orange from aqueous media
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 32 , Volume 61, Issue 32 , 2022 , Pages 11735-11746 ; 08885885 (ISSN) ; Jafarpour, E ; Shojaei, A ; Molavi, H ; Sharif University of Technology
American Chemical Society
2022
Abstract
A series of UiO-66/polyaniline (UiO-66/PANI) nanohybrids with various UiO-66 to aniline weight ratios ranging from 0.01 to 0.1 was synthesized using an in situ polymerization technique. The adsorption behavior of the neat PANI nanofiber network and the synthesized nanohybrids was examined toward anionic methyl orange (MO) dye from aqueous media. It was realized that the maximum adsorption capacity of PANI (229 mg/g) increases steadily by increasing the UiO-66 content in the nanohybrid up to 7 wt % at 426 mg/g, and then, it approximately levels off at 432 mg/g for the nanohybrid sample containing 10 wt % UiO-66, that is, UP10. Based on a thorough characterization, it was shown that UiO-66 is...
Synthesis and Characterization of Electrospun N/S Doped ZnO and Investigation of their Applications in Dye Degradation
, M.Sc. Thesis Sharif University of Technology ; Poujavadi, Ali (Supervisor)
Abstract
In this research, the synthesis of the electrospum nano fiber doped zinc oxide and its photocatalyst usage was investigated. The band gap of the zinc oxide in the area of UV leads to deactivation of this material at the visible light. With due the attention to sunny weather in Iran and the fact that about 50 percentage of sunlight is visible light, producing and usage of catalyst materials actived at visible light is economical. Doping is one of the ways of activating ZnO at visible light, so in this research thiourea is used as the source of ZnO doping. The results of the expriments done at visible light and also spectrums of DRS, XPS and XRD prove that the doping is happened. Also, in this...
Application of Magnetic Grapheme Oxide Coated by Modified Carboxymethyl Cellulose as a Nanoadsorbent to Dye Removal
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor) ; Alamolhoda, Ali Asghar (Supervisor)
Abstract
There are many industries in the world that produce colorized wastewater. Because of the complex structure and good solubility of dyes, such industries have problem treating this wastewaters. On the other hand, because of the toxicity of these materials for water living, dye removal from discharged wastewater of these industries is very important. In recent years, researchers have become interested in the synthesis of dye Nano adsorbents and they have published many works on this subject. The important parameters in the synthesis of such adsorbent include; non-toxicity, high adsorption capacity and easy separation. In this project, cellulose was extracted from bagasse and then CMC was...
Adsorption of Heavy Metals and Various Pollution from Aqueous Solutions by Vegetable Residues
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Seif-Kordi, Ali Akbar (Supervisor)
Abstract
Celery residue modified with H2SO4 was utilized as a low-cost adsorbent for removal of hazardous dyes (methylene blue, malachite green and congo red) and heavy metals (Pb(II) and Cd(II)) from aqueous solution in batch adsorption process. Also, celery residue modified with cationic surfactant (CTAB) to enhance the removal of congo red (anionic dye). The treated and untreated adsorbent was characterized by Fourier transform infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). The efficacy of dye removal of the modified celery residue was investigated by varying adsorbent dose, contact time, pH, initial dye concentration, and temperature. Experimental data were fitted by three...
Ni-doped TiO2 Photoanode Electrodes for Dye-sensitized Solar Cells Applications
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
A new strategy for enhancing the efficiency of TiO2 dye sensitized solar cells (DSSCs) doped with Ni ions with different molar percentages (i.e., 0, 0.5, 1, 5 and 10 mol%) was reported. The samples were prepared by sol-gel route and characterized by means of XRD, DRS, UV-visible, FESEM and photovoltaic measurment techniques. It was found that Ni-doped TiO2 nanoparticles had a mixture of anatase, rutile and brookite crystal structures. Moreover, the band gap energy was decreased with increasing Ni molar ratio, The highest cell efficiency of 5.4% was achieved for 1mol% Ni-doped TiO2, being 42% greater than that of pure TiO2 nanoparticles
Synthesis of Graphene Oxide-based Polymer Nanocomposites and Investigation of Their Ability in Dye Adsorption
, Ph.D. Dissertation Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
In this project, polymer nanocomposites containing graphene oxide were prepared and used for adsorption of several cationic and anionic dyes. In most cases, these nanocomposites were prepared as three-dimentional polymer networks which contain graphene oxide. Nanocomposites with direct grafting of polymer chains onto the surface of graphene oxide were also prepared. Graphene oxide is an oxidized carbonaceous material with unique properties. This material has high surface area, good mechanical strength and various functional groups. Polymeric compounds with different functional groups, structures and properties can be prepared and used. By preparing composites of graphene oxide and polymers,...
Novel organic dyes with anchoring group of barbituric/thiobarbituric acid and their application in dye-sensitized solar cells
, Article Synthetic Metals ; Volume 209 , November , 2015 , Pages 1-10 ; 03796779 (ISSN) ; Salimi Beni, A ; Najafi Chermahini, A ; Ghahary, R ; Teimouri, A ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Abstract New bi-anchoring donor-π-acceptor metal-free organic dyes based on diphenylamine as donor, and barbituric acid and thiobarbituric acid as the acceptor/anchor were synthesized, characterized and used in dye-sensitized solar cells applications. Among the fabricated dye sensitized solar cells, device based on the diphenylamine as donor, and barbituric acid as the acceptor exhibits a high power conversion efficiency of 1.53% with a short circuit current density of 3.71 mA cm-2, an open-circuit photo voltage of 0.55 V and a fill factor of 0.75% under AM 1.5 illumination (85 mW cm-2) compared to the other fabricated devices. The structure of synthesized dyes was optimized and their...