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Total 49 records

    Concurrent photocatalytic degradation and filtration with bi-plasmonic TiO2 for wastewater treatment

    , Article Micro and Nano Letters ; Volume 16, Issue 3 , 2021 , Pages 194-202 ; 17500443 (ISSN) Anvari, A ; Amoli Diva, M ; Sadighi Bonabi, R ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Abstract
    A new photocatalytic filtration membrane was prepared by grafting of Ag–Au bi-plasmonic shell-on TiO2@Fe3O4 nanoparticles as a magnetically-separable heterogeneous photocatalyst to a poly acrylic acid-modified cellulose acetate membrane for decomposition and removal of methyl orange as a model pollutant from textile wastewater samples. Eight photocatalysts including five Au NPs-modified TiO2@Fe3O4 NPs and three Ag-Au bi-plasmonic NPs-decorated TiO2@Fe3O4 NPs with different shell thickness were synthesized and characterized by TEM, UV–vis, and SEM techniques and their photocatalytic activity was assessed using two radiation sources. After selection of optimum photocatalyst and modification of... 

    Enzyme-inspired lysine-modified carbon quantum dots performing carbonylation using urea and a cascade reaction for synthesizing 2-benzoxazolinone

    , Article ACS Catalysis ; Volume 11, Issue 17 , 2021 , Pages 10778-10788 ; 21555435 (ISSN) Hasani, M ; Kalhor, H. R ; Sharif University of Technology
    American Chemical Society  2021
    Abstract
    Catalysts as the dynamo of chemical reactions along with solvents play paramount roles in organic transformations in long-lasting modes. Thus, developing effective and biobased catalysts in nontoxic solvents is highly in demand. In this report, carbon quantum dots (CQDs) functionalized with-lysine (Lys-CQDs) were generated from entirely nature-derived materials; they were demonstrated to be a promising catalyst for C-N bond formation in choline chloride urea (ChCl/U), a natural deep eutectic solvent (NADES). Among a number of synthesized CQDs, Lys-CQD turned out to be a powerful catalyst in the model reaction with aniline to afford phenyl urea. This type of transformation is important... 

    Photocatalytic TiO2@MIL-88A (Fe)/polyacrylonitrile mixed matrix membranes: Characterization, anti-fouling properties, and performance on the removal of natural organic matter

    , Article Chemosphere ; Volume 302 , 2022 ; 00456535 (ISSN) Salehian, S ; Mehdipour, M. H ; Fotovat, F ; Mousavi, S. A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Photocatalytic membrane reactors (PMRs), coupling photocatalysts and membranes in a single system, have shown a considerable potential to reduce membrane fouling, which is one of the major drawbacks of using membranes to treat water and wastewater. In this study, the visible light-activated photocatalysts were incorporated into the polyacrylonitrile (PAN) casting solution to synthesize the photocatalytic composite membranes. The physicochemical properties and the morphology of the membranes and photocatalysts were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction analysis (XRD), ultraviolet–visible diffuse reflectance... 

    Nanofluid preparation, stability and performance for CO2 absorption and desorption enhancement: A review

    , Article Journal of Environmental Management ; Volume 313 , 2022 ; 03014797 (ISSN) Tavakoli, A ; Rahimi, K ; Saghandali, F ; Scott, J ; Lovell, E ; Sharif University of Technology
    Academic Press  2022
    Abstract
    In recent years, the importance of capturing CO2 has increased due to the necessity of minimizing climate change and the detrimental effects of CO2 emissions from industrial processes. CO2 absorption, as one of the most mature carbon capture technologies, has been improved by introducing nanosized particles into liquid absorbents. Nanofluids have been the subject of interest in many studies recently due to their tremendous impact on absorption. This review comprehensively examines the CO2 absorption behavior for nanofluids through the investigation of different absorption systems. Potential mechanisms for improving the absorption/regeneration performance of nanoabsorbents as well as the... 

    Electrospun Ag-decorated reduced GO-graft-chitosan composite nanofibers with visible light photocatalytic activity for antibacterial performance

    , Article Chemosphere ; Volume 299 , 2022 ; 00456535 (ISSN) Asgari, S ; Mohammadi Ziarani, G ; Badiei, A ; Setayeshmehr, M ; Kiani, M ; Pourjavadi, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The treatment of water contaminated by bacteria is becoming a necessity. The nanomaterials possessing both intrinsic antibacterial properties and photocatalytic activity are excellent candidates for water disinfection. The powdered form of nanomaterials can be aggregated while embedding the nanomaterials into the NFs can overcome the limitation and enhance the photocatalytic activity and transition from UV-light to visiblelight. Here, graphene oxide (GO) was synthesized, grafted to chitosan, and decorated with silver nanoparticles (Ag NPs) to produce Ag-decorated reduced GO-graft-Chitosan (AGC) NPs. The blends of polyacrylonitrile (PAN) and AGC NPs were prepared in various concentrations of... 

    SPR-based assay kit for rapid determination of Pb2+

    , Article Analytica Chimica Acta ; Volume 1220 , 2022 ; 00032670 (ISSN) Amirjani, A ; Kamani, P ; Madaah Hosseini, H. R ; Sadrnezhaad, S. K ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    A recyclable optical nanosensor was developed by immobilizing L-tyrosine functionalized silver nanoparticles (AgNPs) on the polyethylene terephthalate (PET) substrate for rapid determination of Pb2+ ions. At first, the L-tyrosine functionalized AgNPs were assessed in the solution phase; the response time was lower than 15 s, and a limit of detection lower than 9 nM was obtained in the dynamic range of 1–1000 nM. For fabrication of the optical assay kit, the design of experiment (DOE) was used to optimize the immobilization efficiency of the nanoparticles on PET films by studying AgNO3 concentration and pH as two crucial parameters. The assay kit in optimal conditions showed a sharp localized... 

    Enhanced singlet oxygen production under nanoconfinement using silica nanocomposites towards improving the photooxygenation’s conversion

    , Article Journal of Nanoparticle Research ; Volume 24, Issue 9 , 2022 ; 13880764 (ISSN) Tamtaji, M ; Kazemeini, M ; Sharif University of Technology
    Springer Science and Business Media B.V  2022
    Abstract
    In this contribution, the effect of physical immobilization of methylene blue (MB) into silica nanocomposites was investigated on the conversion and selectivity of the photooxygenation of anthracene and dihydroartemisinic acid (DHAA). Physically immobilized photocatalysts were synthesized through a developed Stöber method and were thoroughly characterized by UV–Vis, FTIR, XRD, XPS, SEM, TEM, HR-TEM, BET-BJH, and EDX analyses. Based on the TEM and UV–Vis results, it was determined that enhancement of the MB concentration as an organocatalyst for the Stöber reaction led to an increase in the size of the nanoparticles from 54 to 183 nm and a 21 nm blue shift in their UV–Vis spectra. Moreover,... 

    Controlled temperature-mediated curcumin release from magneto-thermal nanocarriers to kill bone tumors

    , Article Bioactive Materials ; Volume 11 , 2022 , Pages 107-117 ; 2452199X (ISSN) Khodaei, A ; Jahanmard, F ; Madaah Hosseini, H. R ; Bagheri, R ; Dabbagh, A ; Weinans, H ; Amin Yavari, S ; Sharif University of Technology
    KeAi Communications Co  2022
    Abstract
    Systemic chemotherapy has lost its position to treat cancer over the past years mainly due to drug resistance, side effects, and limited survival ratio. Among a plethora of local drug delivery systems to solve this issue, the combinatorial strategy of chemo-hyperthermia has recently received attention. Herein we developed a magneto-thermal nanocarrier consisted of superparamagnetic iron oxide nanoparticles (SPIONs) coated by a blend formulation of a three-block copolymer Pluronic F127 and F68 on the oleic acid (OA) in which Curcumin as a natural and chemical anti-cancer agent was loaded. The subsequent nanocarrier SPION@OA-F127/F68-Cur was designed with a controlled gelation temperature of... 

    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) Hasanvandian, F ; 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...