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Sonophotocatalytic degradation of sulfadiazine by integration of microfibrillated carboxymethyl cellulose with Zn-Cu-Mg mixed metal hydroxide/g-C3N4 composite
, Article Separation and Purification Technology ; Volume 245 , 2020 ; Khataee, A ; Vahid, B ; Karimi, A ; Golizadeh, M ; Ritala, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
This research aimed to prepare a recoverable sonophotocatalyst, in which microfibrillated carboxymethyl cellulose (MFC) acted as the Zn-Cu-Mg-mixed metal hydroxide/graphitic carbon nitride (MMH/g-C3N4) carrier. The characteristics of bare and composite sonophotocatalysts were analyzed by the XRD, FT-IR, BET, DRS, PL and FE-SEM equipped with the EDX mapping. The performance of prepared composites (MMH/g-C3N4@MFC) with various weight ratios of the MMH/g-C3N4 was studied for the sonophotocatalytic degradation of sulfadiazine (SDZ) as the model emerging contaminant. 93% of SDZ was degraded using the most effective catalyst (MMH/g-C3N4@MFC3) with 15% weight ratio of the MMH/g-C3N4 under the...
One-pot microwave synthesis of hierarchical C-doped CuO dandelions/g-C3N4 nanocomposite with enhanced photostability for photoelectrochemical water splitting
, Article Applied Surface Science ; Volume 530 , 2020 ; Siavash Moakhar, R ; Soleimani, F ; Sadrnezhaad, S. K ; Masudy Panah, S ; Katal, R ; Seza, A ; Ghane, N ; Ramakrishna, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Cupric oxide (CuO) is a semiconductor of choice for photocathode in photoelectrochemical (PEC) applications due to its great sunlight absorption capability. However, photocorrosion is the main drawback of CuO. Herein, CuO/graphitic carbon nitride (g-C3N4) with a unique microstructure, enhanced PEC performance, and considerable photostability is synthesized under microwave irradiation. A facile, one-pot method is utilized to directly deposit the nanocomposite onto fluorine-doped tin oxide from a solution containing copper precursor and urea. Possible mechanism of CuO/g-C3N4 formation through this novel method is investigated. It is elucidated that controlled amounts of urea critically...
Enhanced photocatalytic activity of ZnO/g-C3N4 nanofibers constituting carbonaceous species under simulated sunlight for organic dye removal
, Article Ceramics International ; Volume 47, Issue 18 , 2021 , Pages 26185-26196 ; 02728842 (ISSN) ; Samadi, M ; Pourjavadi, A ; Ramakrishna, S ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Semiconductor-based photocatalysis is an efficient approach for degradation of organic pollutants. In this context, ZnO/g-C3N4 composite nanofibers containing carbonaceous species with different concentrations of g-C3N4 nanosheets (x = 0.25, 0.5, 1, 2, 10 wt%) noted as ZnO/carbon/(x wt%) g-C3N4 are prepared by electrospinning technique. For preparation of the composite nanofibers, bulk g-C3N4 is exfoliated to nanosheets, and then it is mixed with polyvinyl alcohol and appropriate zinc acetate content followed by electrospinning process. Thermal annealing of the as spun zinc acetate/poly(vinyl alcohol)/g-C3N4 nanosheets sample under N2 atmosphere leads to the formation of carbonaceous species...
Nanorod carbon nitride as a carbo catalyst for selective oxidation of hydrogen sulfide to sulfur
, Article Journal of Hazardous Materials ; Volume 364 , 2019 , Pages 218-226 ; 03043894 (ISSN) ; Eskandari, M. M ; Rashidi, A ; Baghalha, M ; Hassanisadi, M ; Hamzehlouyan, T ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Two-dimensional mesoporous carbon nitride and its highly efficient nanorod framework were prepared via hard-templating method. The obtained materials were fully characterized. The results showed that the samples structural ordering and morphology were similar to those of the parent silica templates; they had large pore volumes as well as high surface area structures. Carbon nitride carbocatalysts were used for H2S selective oxidation. The catalytic tests were carried out at 190, 210 and 230 °C in a fixed bed reactor. The obtained selectivity values for mesoporous carbon nitride rod and mesoporous carbon nitride toward elemental sulfur at 190 °C were 88.8% and 83%, respectively. Both samples...
Degradation of Model Textile Dyes in Wastewater using Visible-Light Active Photocatalysts
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Vossoughi, Manouchehr (Co-Supervisor) ; Padervand, Mohsen (Co-Supervisor)
Abstract
Textile dyes are a major category of organic pollutants and release of them in the environment causes serious problems. Among the most commonly used methods for colored wastewater, advanced oxidation processes, especially the photocatalytic process, are rapidly developing as a new and effective solution. However, there is still a need for high-level photocatalytic activity and improvement of this process to increase removal efficiency. In this study, we have tried to provide a higher performance for color removal using carbon nitride photocatalyst. Accordingly, two approaches have been proposed to improve the removal of rhodamine b, as one of the common dyes in the textile industries. The...
Kinetics of Adsorption of DBT Sulfur Containing Compound of Gasoline via Nanostructured Adsorbent
, M.Sc. Thesis Sharif University of Technology ; Sadrnezhad, Khatiboleslam (Supervisor)
Abstract
Based on the new standards, less than 10 ppm sulfur is allowed for the automotive fuels. This has led researchers to try improving the present conventional methods as well as seeking alternative routes for refinement of the petroleum products so much to comply with the requirements. Since thiophenic fragments such as dibenzothiophene (DBT) are the most durable sulfur compounds in the current hydrodisulfurization method, many studies have been conducted over recent years on how to remove these compounds. In this thesis, the desulfurization of dibenzothiophene from gasoline via adsorption method was studied. In order to carry out the adsorption process, a nanocomposite of graphitic-carbon...
Synthesis of the Graphitic Carbon Nitride/Iron Oxide Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Sadrnezhad, Khatiboleslam (Supervisor)
Abstract
The g-C3N4/Fe2O3 nanocomposite was produced by the combustion synthesis. The product was characterized by x-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller study (BET), Ultraviolet-visible analysis (UV-vis) and photoluminescence measurement (PL). Effect of iron nitrate on stability and photocurrent density under simulated visible-light irradiation was determined. The highest photocurrent density obtained (4.25 μA/Cm2) was twelve times the pure g-C3N4. This improvement was due to a bandgap decrease, the specific surface area increase, reduction of the electron-hole recombination, and...
Copper Oxide/g-C3N4 Nanocomposites: Synthesis and Optical and Photocatalytic Properties Investigation
, M.Sc. Thesis Sharif University of Technology ; Sadrnezhaad, Khatiboleslam (Supervisor)
Abstract
Herein, cupric oxide (CuO)/graphitic carbon nitride (g-C3N4) is synthesized under microwave irradiation for enhanced photoelectrochemical (PEC) performance and photostability. A facile, one-pot method was utilized to directly deposit the nanocomposite onto FTO from a solution containing copper precursor and urea. Possible mechanisms of CuO/g-C3N4 formation and PEC performance improvement were examined via XRD, FTIR, FESEM, XPS, UV-Vis, and PL. Controlled amounts of urea determined the morphological evolution of CuO and the formation of a protective carbon layer, while its excess quantity converted to g-C3N4 in the presence of CuO. Through heat treatment of the nanocomposite, carbon-doped...
Degradation of Organic Pollutants in Water by Advanced Oxidation Process Using MIL-based Nanostructured Catalyst
, M.Sc. Thesis Sharif University of Technology ; Kazemini, Mohammad (Supervisor) ; Mahmoodi, Nyaz Mohammad (Supervisor)
Abstract
Octahedral crystals of Fe-Metal-organic frameworks like Fe-MIL-101, which is the most stable and active metal-organic frameworks; in combination with graphitic carbon nitride nanosheets could significantly enhance the photocatalytic activity of g-C3N4 for inorganic dye degradation under the irradiation of visible light application. This appropriate cocatalyst modifies the performance of semiconductor via suppressing the recombination of photo-induced carriers and since the synthesized composite prepared by in-situ procedure possesses close contact between each other, the migration of electrons in the photocatalytic reaction will be continued, so the degradation process via the active species...
Synthesis and Characterization of Core-shell Nanoparticles Anchored Reduced Graphene Oxide (rGO) and Kinetic Investigation of Oxygen Evolution from Water Oxidation in the Presence of these Nanocatalysts
, M.Sc. Thesis Sharif University of Technology ; Rahman Setayesh, Shaherbanoo (Supervisor) ; Taherinia, Davood (Co-Supervisor)
Abstract
The reaction of oxygen evolution, in other words, the process of water oxidation in the presence of heterogeneous photocatalysts such as g-C3N4, Co/g-C3N4 /rGO, Ni/g-C3N4/rGO, CoNi/g-C3N4 / rGO, Co2Ni1/g-C3N4/rGO, and Co1Ni2 /g-C3N4 /rGO were studied. The characterization of these nanocatalysts was done by XRD, SEM, FT-IR, BET, DRS, CHN, and TGA techniques. Thermogravimetric analysis (TGA) was used to check the thermal stability of these nanocatalysts. The FT-IR spectroscopy was used to identify the functional groups in graphitic carbon nitride and to confirm g-C3N4 synthesis. According to BET results, the pore sizes were determined which were at the nano and macro scale. It was found that...
The Morphological Effects of Surface Modified Mos2 Nanosheets and Mos2 Qd/G-C3n4 Heterostructure Prepared by Chemical Methods in Hydrogen Evolution Reaction (Her)
, Ph.D. Dissertation Sharif University of Technology ; Moshfegh, Alireza (Supervisor) ; Naseri, Naeimeh (Co-Supervisor)
Abstract
The sustainable development in societies and the global energy challenge requires usage of clean energy systems that have attracted the attention of many researchers in recent decades. One of the major challenges in generating renewable resources is the problem of energy storage and imbalance between supply and demand cycles. Hydrogen as one of the clean energy carriers and due to having the highest energy density in terms of weight, is one of the important research topics. From this point of view, the preparation of electrocatalysts for hydrogen production, based on available materials, via simple and environmentally friendly production methods, was considered in this research....
Synthesis and Characterization of g-C3N4 Containing Composite Scaffolds for Bifunctional Anti-Cancer/Tissue Engineering Application
, M.Sc. Thesis Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor)
Abstract
Today, due to changes in lifestyle and environmental changes, the incidence of cancer is increasing worldwide. With the advancement of science and technology, humans have always sought ways to improve their quality of life and lifespan. The most common cancer related to bone tissue is osteosarcoma. One of the most effective treatment methods is photodynamic therapy. This method requires a photosensitizer with appropriate optical and biological properties. The ideal photosensitizer should be excited with light in the NIR range and produce ROS or active oxygen species. In this research, oxygen-doped graphitic carbon nitride modified by heterojunction with Mn3O4 was used as a photosensitizer....
Synthesis and Characterization of the Multifunctional Fe3O4@Mn3O4-LCysteine-g-C3N4 QDs System as a Contrast Agent for Dual-Model Magnetic Resonance and Fluorescence Imaging
, M.Sc. Thesis Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor) ; Khachatourian, Adrine Malek (Supervisor)
Abstract
Cancer is one of the most important problems that affects public health. If this disease is diagnosed quickly in the patient's body, it can be prevented and treated by determining the stage of the disease and establishing a treatment protocol. Magnetic resonance imaging (MRI) and fluorescence imaging (FI) are among the imaging methods. In order to increase the contrast of images, researchers have turned to the synthesis of materials under contrast agents, which improve diagnostic sensitivity. Synthesis of nanoparticles as multi-mode contrast agents can enhance imaging methods. In this research, the synthesis and characterization of the multifunctional Fe3O4-Mn3O4-LCysteine@g-C3N4 QDs system...
Ultrahigh permeable C2N-inspired graphene nanomesh membranes versus highly strained c2n for reverse osmosis desalination
, Article Journal of Physical Chemistry B ; Volume 123, Issue 41 , 2019 , Pages 8740-8752 ; 15206106 (ISSN) ; Akhavan, O ; Sharif University of Technology
American Chemical Society
2019
Abstract
The reverse osmosis (RO) desalination capability of hydrogenated and hydroxylated graphene nanomesh membranes (GNMs) inspired by the morphology of carbon nitride (C2N) has been studied by using molecular dynamics simulation. As an advantage, water permeance of the GNMs is found to be several orders of magnitude higher than that of the available RO filters and comparable with highly strained C2N (S-C2N) as follows: 6,6-H,OH > 12-H > S-C2N > 5,5-H,OH > 10-H. The reverse order is found for salt rejection, regardless of S-C2N. The hydrophilic character of the incorporated -OH functional group is believed to be responsible for linking the water molecules in feed and permeate sides via the...
Enhanced decolorization of rhodamine B solution through simultaneous photocatalysis and persulfate activation over Fe/C3N4 photocatalyst
, Article Chemical Engineering Research and Design ; Volume 153 , 2020 , Pages 709-720 ; Padervand, M ; Soltanieh, M ; Vossoughi, M ; Sharif University of Technology
Institution of Chemical Engineers
2020
Abstract
In this study, organic contaminant degradation was intensified by increasing the oxidative capacity of the reaction system through simultaneous photocatalysis and heterogeneous persulfate activation. Fe nanoparticles were served as a multifunctional modifier to enhance the photoactivity of graphitic carbon nitride (CN), by tuning optical properties as well as persulfate (PS) activation rate, by introducing a new activation pathway. The synthesized photocatalysts were characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), UV-visible...
Encapsulation of spinel CuCo2O4 hollow sphere in V2O5-decorated graphitic carbon nitride as high-efficiency double Z-type nanocomposite for levofloxacin photodegradation
, Article Journal of Hazardous Materials ; Volume 423 , 2022 ; 03043894 (ISSN) ; Shokri, A ; Moradi, M ; Kakavandi, B ; Rahman Setayesh, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this study, spinel CuCo2O4 (CCO) with a hierarchical hollow sphere morphology was encapsulated in V2O5-decorated ultra-wrinkled graphitic carbon-nitride (VO-UCN) for the first time via a facile glycerol-assisted solvothermal method in the interest of developing a novel high-efficiency double Z-type nano-photocatalyst (denoted as VO-UCN@CCO). The remarkable physicochemical features of the as-prepared nano-photocatalysts were verified using diverse characterization techniques including TGA, XRD, FT-IR, FE-SEM, TEM, BET, UV–vis DRS, PL, EIS, and transient photocurrent techniques. Herein, VO-UCN@CCO nanocomposite was employed for the photodisintegration of levofloxacin (LVOF) antibiotic under...
Theoritical Investigation of Metallic Cations and Gas Adsorption on Surface of Carbon Nanostructures
, Ph.D. Dissertation Sharif University of Technology ; Tafazoli, Mohsen (Supervisor) ; Shamkhali, Amir Nasser (Supervisor)
Abstract
Carbon nanostructures are of great importance in scientific and industrial research. Two case of the important two-dimensional carbon nanostructures are graphitic carbon nitride (g-C3N4) and graphene. In the first part of this work, adsorption of important heavy metal cations including Hg+2, Ag+, Cr+3, Pb+2, Cu+2, Ni+2, Cd+2, Tl+, Sb+3, Zn+2 and As+3 on the surface of (g-C3N4) was investigated by density functional theory (DFT). The main purpose of this theoretical study is to evaluate the ability of g-C3N4 to adsorb pollutant cations. The most prominent result of this work was the ability of g-C3N4 for effective adsorption of As+3 and Sb+3 ions from aqeous solutions. Also, another...
Performance Modeling of Nano-Porous Monolayers in Water Desalination Using Molecular Dynamics Simulations Approach
, Ph.D. Dissertation Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Nejat, Hossein (Co-Supervisor)
Abstract
Water plays an essential role in the daily lives of humans, plants, and animals. Due to the lack of safe water on the planet, in recent years there have been many challenges in the field of water treatment, which has made water desalination technology always one of the most advanced technologies. The most advanced technology in this field is the use of nanotechnology in water and wastewater treatment, especially the use of Membrane processes such as reverse osmosis. Unlike conventional reverse osmosis membranes, nanoporous membranes can ensure rapid water transfer during the displacement process. The purpose of this thesis is to introduce new monolayers that have an incredible performance in...
Chromium carbonitride coating produced on DIN 1.2210 steel by thermo-reactive deposition technique: Thermodynamics, kinetics and modeling
, Article Surface and Coatings Technology ; Volume 225 , 2013 , Pages 1-10 ; 02578972 (ISSN) ; Nazari, A ; Khoie, S. M. M ; Khalaj, M. J ; Pouraliakbar, H ; Sharif University of Technology
2013
Abstract
A duplex surface treatment on DIN 1.2210 steel has been developed involving nitriding and followed by chromium thermo-reactive deposition (TRD) techniques. The TRD process was performed in molten salt bath at 550, 625 and 700°C for 1-14h. The process formed a thickness up to 9.5μm of chromium carbonitride coatings on a hardened diffusion zone. Characterization of the coatings by means of scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) indicates that the compact and dense coatings mainly consist of Cr(C,N) and Cr2(C,N) phase. All the growth processes of the chromium carbonitride obtained by TRD technique followed a parabolic kinetics. Activation energy (Q) for the...
Synthesis of BiOI/ZnFe2O4-Metal-Organic Framework and g-C3N4-Based Nanocomposites for Applications in Photocatalysis
, Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 23 , 2019 , Pages 9806-9818 ; 08885885 (ISSN) ; Gholami, M. R ; Sharif University of Technology
American Chemical Society
2019
Abstract
A novel binary BiOI/ZnFe2O4 (BZ) with p-n heterojunction based on the different metal-organic framework (MOF) MIL-88B(Fe) and graphite carbon nitride (g-C3N4) as substrates has been designed. As-prepared ternary nanocomposites have been first obtained via a simple hydrothermal system and subsequently deposited onto the MOF and g-C3N4 substrates. The photoactivity of the ternary nanocomposites was evaluated by organic pollutants degradation under LED light. These characterization results indicated that BiOI as a p-type semiconductor was well deposited on the surface of ZnFe2O4 (n-type semiconductors). The p-n heterojunction photocatalyst (BZ) improved the valence band potential of ZnFe2O4 and...