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    Removal of an organic pollutant from waste water by photocatalytic behavior of AgX/TiO2 loaded on mordenite nanocrystals

    , Article Research on Chemical Intermediates ; Volume 38, Issue 8 , 01 September , 2012 , pp 1975-1985 ; 1568-5675 Padervand, M. (Mohsen) ; Salari, H. (Hadi) ; Ahmadvand, S. (Seyed Saeid) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Abstract
    Mordenite (MOR) nanocrystals were synthesized using the hydrothermal method. Sol–gel and deposition methods were utilized to modify the zeolite surface with TiO2 and then AgBr or AgCl particles. Photocatalysts were characterized by using X-ray diffraction, Brunauer–Emmett–Teller (BET), and scanning electron microscopy techniques. Activity was evaluated by photodegradation of Acid Blue 92 as an azo dye. The effect of silver halide deposition on the photocatalytic behavior of the prepared nanocomposites was studied under both ultraviolet (UV) and visible light, and the results were compared. The results showed that AgCl/TiO2/MOR was more active under UV, while with visible source,... 

    Effective photocatalytic degradation of an azo dye over nanosized Ag/AgBr-modified TiO2 loaded on zeolite

    , Article Journal Chemical Papers ; Volume 65, Issue 3 , June , 2011 , pp 280-288 ; 1336-9075 Padervand, M. (Mohsen) ; Tasviri, M. (Mahboubeh) ; Gholami, M. R. (Mohammad Reza) ; Sharif University Of Technology
    Abstract
    Zeolite-based photocatalysts were prepared by the sol-gel and deposition methods. The photocatalysts were characterised by X-ray diffraction, nitrogen adsorption-desorption isotherms, FTIR spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectrometry. The activity of the prepared photocatalysts was evaluated by the UV-induced degradation of acid blue 92, a textile dye in common use. The effect of various parameters, such as catalyst concentration, initial dye concentration, thiosulphate concentration and pH, on the rate and efficiency of the photocatalytic degradation of acid blue 92 was investigated. The results showed that each parameter influenced the degradation... 

    In-situ formation and entrapment of Ag/AgCl photocatalyst inside cross-linked carboxymethyl cellulose beads: A novel photoactive hydrogel for visible-light-induced photocatalysis

    , Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 398 , 2020 Heidarpour, H ; Golizadeh, M ; Padervand, M ; Karimi, A ; Vossoughi, M ; Tavakoli, M. H ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this work, a novel photoactive cellulose-based hydrogel was prepared by simultaneous AgCl formation and entrapment inside Al (III) and Fe (III) cross-linked carboxymethyl cellulose beads. Physio-chemical and optical properties of the synthesized composites were well characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, elemental mapping, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL), and diffuse reflectance spectroscopy (DRS). The photocatalytic activity of hydrogels was evaluated by the degradation of rhodamine B (RhB), as a model environmental pollutant. A comparative study showed that... 

    Photocatalytic degradation of dibenzothiophene using La/PEG-modified TiO2 under visible light irradiation

    , Article Research on Chemical Intermediates ; Jan , 2014 , pp. 1-17 Moradi, S ; Vossoughi, M ; Feilizadeh, M ; Zakeri, S. M. E ; Mohammadi, M. M ; Rashtchian, D ; Yoosefi Booshehri, A ; Sharif University of Technology
    Abstract
    While the photocatalytic degradation of various organic compounds under UV light irradiation has been widely investigated, visible-light-induced photocatalytic degradation of low levels of pollutants such as dibenzothiophene (DBT) is occasionally reported. In the present work, lanthanide/polyethylene glycol-modified TiO2 (La/PEG/TiO2) has been successfully synthesized by a sol-gel method. The photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-Vis diffusive reflectance spectroscopy, and energy dispersive X-ray analysis. Moreover, the photocatalytic degradation of DBT under visible light irradiation is investigated for the... 

    Kinetic Investigation of Photodegradation of Acid Orange 7 Over AgBr/TiO2 Nanocomposite under UV Light Illumination

    , M.Sc. Thesis Sharif University of Technology Banijamali, Fatemeh (Author) ; Rahman Setayesh, Shahrbanoo (Supervisor) ; Gholami, Mohammad Reza (Supervisor)
    Abstract
    TiO2, Ag/TiO2 and AgBr/TiO2 synthesized by sol – gel method. Synthesized samples were characterized by X- Ray diffraction (XRD) , Fourier transformed infrared ( FT – IR) , Scanning electron microscopy ( SEM) techniques. The results of XRD showed that the particle size is in the nanorange and anatase form of titania is present in all of the photocatalysts. Kinetics of photocatalytic degradation of an azo dye (Acid Orange 7) on photocatalysts was studied. The effect of various parameters such as dye concentration, amount of photocatalyst( AgBr/TiO2) and pH of solution on the rate and efficiency of degradation of Acid Orange 7 was studied. The optimized conditions ( [AgBr/TiO2]= 100 ppm,... 

    Photocatalytic Degradation of Dye in Wastewater Using Nanomaterials Based Zinc-iron

    , M.Sc. Thesis Sharif University of Technology Rezaei, Salar (Author) ; Kazemeini, Mohammad (Supervisor) ; Mahmudi, Niaz Mohammad (Co-Supervisor) ; Baqalha, Morteza (Co-Supervisor)
    Abstract
    Removing pollutants of water and, in general, wastewater treatment is one of the most important issues in the world. In this research, we synthesized a nanophotocatalyst based on znic-iron in the form of a magnetic core-shell Fe3O4@ZIF-8, and used to degrade the malachite green toxic color of wastewater. SEM, XRD and FT-IR analyzes have been taken and analyzed fore all three core, shell and core-shell composite catalysts.Due to the band gap of core-shell nanocomposite and the performance of the malachite green dye, a photocatalytic process under the visible light was obtained, which at an optimum amount of photocatalyst 0.003g, we reach 99.2% dye degradation at the 30ppm concentration. This... 

    Kinetics Investigation of the Photocatalytic Degradation of Acid Blue 92 in Aqueous Solution Using Nanocrystalline TiO2 Prepared in an Ionic Liquid

    , Article Progress in Reaction Kinetics and Mechanism ; vol, 34 , March , 2009 , PP. 55–76 Ghasemi, S. (Shahnaz) ; Rahimnejad, S. (Sara) ; Rahman Setayesh, S. (Shahrbanoo) ; Hosseini, M. (Mohammad) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Abstract
    TiO2 nanoparticles were prepared by the sol - gel process using 2-hydroxylethy- lammonium formate as an ionic liquid. Nanoparticles were crystallized at various temperatures (300-700°C). The products were characterized using X-ray diffraction (XRD), nitrogen adsorption - desorption isotherms and scanning electron microscopy (SEM) techniques. It was found that the resulting TiO2 nanoparticles had good thermal stability either to resist collapse or the anatase-to-rutile phase transformation during heat treatment. The photocatalytic activity of the nanocrystalline TiO2 was evaluated by the degradation of Acid Blue 92 (AB92) which is\ commonly used as a textile dye. The results showed that the... 

    Synthesis and Photocatalytic Performance Study of Ag/Polydopamine Graphitic Carbon Nitride Nanocomposite

    , M.Sc. Thesis Sharif University of Technology Shahsavandi, Faezeh (Author) ; Madaah Hosseini, Hamid Reza (Supervisor)
    Abstract
    Developing an efficient visible-light-driven photocatalyst is believed to be a practical solution for clean energy and environmental remediation. The present study aimed to broaden current knowledge of the graphitic carbon nitride (g-C3N4)-based plasmonic photocatalysts by decorating polydopamine-grafted g-C3N4 (PDA/g-C3N4) with silver nanoparticles (AgNPs). The ternary nanocomposite was prepared using a facile synthesis method, while XPS and electron microscopy measurements confirmed the homogenous dispersion of AgNPs on PDA/g-C3N4. It was revealed that AgNPs successfully reduced the recombination rate of photoinduced electron-hole charge carriers. The calculated bandgap energy was... 

    Response surface analysis of photocatalytic degradation of methyl tert-butyl ether by core/shell Fe3O4/ZnO nanoparticles

    , Article Journal of Environmental Health Science and Engineering ; Vol. 12, issue. 1 , 2014 Safari, M ; Rostami, M. H ; Alizadeh, M ; Alizadehbirjandi, A ; Nakhli, S. A. A ; Aminzadeh, R ; Sharif University of Technology
    Abstract
    The degradation of methyl tert-butyl ether (MTBE) was investigated in the aqueous solution of coated ZnO onto magnetite nanoparticale based on an advanced photocatalytic oxidation process. The photocatalysts were synthesized by coating of ZnO onto magnetite using precipitation method. The sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibration sample magnetometer (VSM). Besides, specific surface area was also determined by BET method. The four effective factors including pH of the reaction mixture, Fe3O4/ZnO magnetic nanoparticles concentration, initial MTBE concentration and molar ratio of [H2O2]/ [MTBE] were optimized using response surface... 

    , M.Sc. Thesis Sharif University of Technology Hassanjani, Sina (Author) ; Alemzadeh, Iran (Supervisor) ; Vosoughi, Manouchehr (Co-Advisor)
    Abstract
    Nowadays with the extension of industry and factories as well as different kinds of plants, a wide range of pollution and circumference hazardous has been entered to the people`s life. Industrial wastewater has been always a threat for health of our environment and efforts for reducing its dangerous effects are still under studies. Dairy wastewater is one of the main branches of food industrial pollutions and it has been studied in this specific project. The goal was to reduce the Chemical Oxygen Demands (COD) of dairy wastewater with oxidation of Titanium Dioxide Nanophotocatalyst oxidation under UV irradiation. Among the various methods for synthesizing of this Nanophotocatalyst, the... 

    Kinetic Investigation of the Degradation of Environmental Pollutant in the Presence of TiO2 Nanoparticle on Carbon Nanotube

    , M.Sc. Thesis Sharif University of Technology Rashedi, Zahra (Author) ; Gholami, Mohammad Reza (Supervisor) ; Rahman Setayesh, Shahrbanoo (Co-Advisor)
    Abstract
    The present work is based on the, synthesis and investigation of photocatalytic activity of TiO2, TiO2/MWCNT, ZnO and ZnO/MWCNT nanostructures. The nanostructures were prepared using multi-walled carbonnanotubes (MWCNT) as templates.The SEM images of TiO2 and ZnO nanoparticles and TiO2/MWCNT andZnO/MWCNT showed that nanosize TiO2 and ZnO particles homogeneously and densely supported on the surfaces of multiwall carbon nanotubes the photocatalytic activity of the TiO2, TiO2 /MWCNT, ZnO and ZnO/MWCNT was examined by the degradation of Basic Blue 41(BB41) under UV and Vis lights. The optimum conditions for degradation of BB41 on TiO2 where found to be: calcination temperature (450 °C), dye... 

    Evaluation and modeling of a newly designed impinging stream photoreactor equipped with a TiO2 coated fiberglass cloth

    , Article RSC Advances ; Volume 5, Issue 12 , 2015 , Pages 9019-9027 ; 20462069 (ISSN) Jafarikojour, M ; Mohammadi, M. M ; Sohrabi, M ; Royaee, S. J ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    The photocatalytic degradation of p-nitrophenol (PNP) using TiO2 particles immobilized on a fiberglass cloth was investigated in a novel design of a photo-impinging stream reactor. A spray painted method has been used for the coating process. The structural properties of the immobilized sample were examined using X-ray diffraction and a scanning electron microscope (SEM). The photocatalytic degradation results showed the good performance of the reactor. The flow regime within the reactor was characterized and modeled by applying a liquid residence time distribution. A compartment model consisting of four continuous stirred regions was assigned to describe the flow pattern in the reactor. A... 

    Investigation of 2-nitrophenol solar degradation in the simultaneous presence of K2S2O8 and H2O2: Using experimental design and artificial neural network

    , Article Journal of Cleaner Production ; Volume 176 , 2018 , Pages 1154-1162 ; 09596526 (ISSN) Bararpour, S. T ; Feylizadeh, M. R ; Delparish, A ; Qanbarzadeh, M ; Raeiszadeh, M ; Feilizadeh, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this study, the interaction effect of K2S2O8 (PDS) and H2O2 (as two powerful oxidants) was investigated on the solar degradation of 2-nitrophenol (2-NF) in the two systems, i.e. absence and presence of Ag/S/TiO2 photocatalyst. Experiments were designed based on the central composite design, and two methods of response surface methodology (RSM) and artificial neural network (ANN) were developed for modeling of the systems. Concentrations of PDS and H2O2 were considered as independent variables and 2-NF degradation efficiency was selected as the response. It was revealed that the predictive capacity of ANN model is more than RSM model according to their corresponding R2, R2 adj RMS, MAE,... 

    Tuning composition of electrospun ZnO/CuO nanofibers: toward controllable and efficient solar photocatalytic degradation of organic pollutants

    , Article Journal of Physical Chemistry C ; Volume 121, Issue 6 , 2017 , Pages 3327-3338 ; 19327447 (ISSN) Naseri, A ; Samadi, M ; Mahmoodi, N. M ; Pourjavadi, A ; Mehdipour, H ; Moshfegh, A. Z ; Sharif University of Technology
    American Chemical Society  2017
    Abstract
    ZnO/CuO nanofibers, with different CuO concentrations, were fabricated by one-step electrospinning of the polymer precursor and annealing in air. Scanning electron microscopy (SEM) showed smooth and beadless morphology for the synthesized nanofibers, while X-ray diffraction (XRD) analysis revealed formation of hexagonal and monoclinic crystalline structure phases for ZnO and CuO nanofibers, respectively. X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of CuO on the surface of ZnO nanofibers. For further confirming the formation of chemical bonds, Fourier transform infrared (FT-IR) spectroscopy was employed. The effect of Cu contents in the overall electronic band... 

    Photocatalytic Dye Degradation of Wastewater Using Copper Composite Nanophotocatalyst by Advanced Oxidation Process

    , M.Sc. Thesis Sharif University of Technology Rezaei, Pardis (Author) ; Ghotbi, Cyrus (Supervisor) ; Mahmoodi, Niyaz Mohammad (Supervisor) ; Kazemeyni, Mohammad (Supervisor)
    Abstract
    Azo dyes that are the most common dyes in textile industries, are toxic and stable complex compounds. Release of this dyes in environment disturb the ecosystem and endanger human health. So selection of an appropriate method for treatment of them is a sensitive work. photocatalytic degradation is one of the best promising methods because of its perfect mineralization, middle condition and lack of creating the secondary pollutant. In this research CuO/CNT nanocomposite was synthesized and used as a photocatalyst. The surface features of CuO/CNT were surveyed by using Fourier transform infrared(FTIR), X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Photocatalytic efficiency of... 

    Synthesis of Mof-Based Magnetic Nanocomposites and their Capability for Organic Dye Degradation in Water Via Photocatalysis Process

    , Ph.D. Dissertation Sharif University of Technology Bagherzadeh Hosseini, Behnam (Author) ; Kazemeini, Mohammad (Supervisor) ; Mahmoodi, Niyaz Mohammad (Supervisor)
    Abstract
    Photocatalytic as well as photo-Fenton-like processes are promising and ideal technologies for using solar energy to regenerate energy as well as regenerate and revitalize the environment. In fact, photocatalytic processes are one of the most important chemical methods to reduce energy and environmental crises by converting endless solar energy into pure chemical potential. Photocatalytic processes and photocatalysts based on metal-organic frameworks (MOFs) have attracted special attention in recent years due to their excellent and unique properties such as adjustable structure and optical properties. In fact, metal-organic frameworks, as a group of newly emerged crystalline porous... 

    Photocatalytic Degradation of Organic Pollutants in the Presence of Nanocomposites Based on Graphitic Carbon Nitride under Visible Light Illumination

    , M.Sc. Thesis Sharif University of Technology Hasanvandian, Farzad (Author) ; Hamzehlouyan, Tayebeh (Supervisor) ; Rahman Setayesh, Shahrbanoo (Co-Supervisor)
    Abstract
    The susceptible light-harvesting and tremendous reduction capability along with the potentiality (photo)electrochemical merits of the thiospinels like CuCo2S4 (CCS) bring forth appreciably an advancement in efficacious photocatalytic reactions. However, scant oxidation potential originated from 3p orbitals of sulfur atoms puts a damper on their performance and is even conducive to self-oxidation. In this research, the surfactant/template free of hierarchical CCS thiospinels was synthesized using solvothermal sulfidation of the affordable glycerate-based CuCo-alkoxide and successfully was embedded with Z-scheme V2O5 deposited on wrinkled g-C3N4 lamella (VO-UCN) in the interest of developing... 

    Photocatalytic degradation of dibenzothiophene using La/PEG-modified TiO2 under visible light irradiation

    , Article Research on Chemical Intermediates ; Volume 41, Issue 7 , July , 2015 , Pages 4151-4167 ; 09226168 (ISSN) Moradi, S ; Vossoughi, M ; Feilizadeh, M ; Zakeri, S. M. E ; Mohammadi, M. M ; Rashtchian, D ; Yoosefi Booshehri, A ; Sharif University of Technology
    Kluwer Academic Publishers  2015
    Abstract
    While the photocatalytic degradation of various organic compounds under UV light irradiation has been widely investigated, visible-light-induced photocatalytic degradation of low levels of pollutants such as dibenzothiophene (DBT) is occasionally reported. In the present work, lanthanide/polyethylene glycol-modified TiO2 (La/PEG/TiO2) has been successfully synthesized by a sol-gel method. The photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-Vis diffusive reflectance spectroscopy, and energy dispersive X-ray analysis. Moreover, the photocatalytic degradation of DBT under visible light irradiation is... 

    Recent progress on doped ZnO nanostructures for visible-light photocatalysis

    , Article Thin Solid Films ; Volume 605 , April , 2015 , Pages 2–19 ; 00406090 (ISSN) Samadi, M ; Zirak, M ; Naseri, A ; Khorashadizade, E ; Moshfegh, A. Z ; Sharif University of Technology
    Elsevier  2015
    Abstract
    Global environmental pollution and energy supply demand have been regarded as important concerns in recent years. Metal oxide semiconductor photocatalysts is a promising approach to apply environmental remediation as well as fuel generation from water splitting and carbon dioxide reduction. ZnO nanostructures have been shown promising photocatalytic activities due to their non-toxic, inexpensive, and highly efficient nature. However, its wide band gap hinders photo-excitation for practical photocatalytic applications under solar light as an abundant, clean and safe energy source. To overcome this barrier, many strategies have been developed in the last decade to apply ZnO nanostructured... 

    Acid blue 92 photocatalytic degradation in the presence of scavengers by two types photocatalyst

    , Article Environmental Progress and Sustainable Energy ; Volume 31, Issue 3 , 2012 , Pages 371-378 ; 19447442 (ISSN) Elahifard, M. R ; Gholami, M. R ; Sharif University of Technology
    Abstract
    Two types of nanosized photocatalyst, TiO 2 P-25 and ap/Ag/AgBr/TiO 2, were used for decolorization of Acid Blue 92 (AB92) in dark, visible light (V-L), and UV media. Under UV and V-L, the effect of three possible photodegradation processes of AB92 including photocatalytic degradation, self-photosensitization, and direct photolysis were studied. Results showed that in UV/photocatalysts, photocatalytic degradation is the major process for photodecolorization. However, in the presence of TiO 2, self-photosensitization has the major role under V-L. Because of the presence of AgBr as photoactive center in ap/Ag/AgBr/TiO 2, the main process is the photocatalytic degradation in V-L. By using...