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  • Article

    1 - Enhanced photocatalytic activity of sonochemical derived ZnO via the co-doping process
    Iranian Journal of Catalysis , Issue 5 , Year , Winter 2016
    In the present study, Co-ZnO and Co-Ni-ZnO nanoparticles were synthesized by sonochemical methods and the structural and optical properties were investigated through Fourier Transform Infrared spectroscopy (FTIR), UV-Vis spectroscopy, Field Emission Scanning Electron Mi More
    In the present study, Co-ZnO and Co-Ni-ZnO nanoparticles were synthesized by sonochemical methods and the structural and optical properties were investigated through Fourier Transform Infrared spectroscopy (FTIR), UV-Vis spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), X-Ray Diffraction (XRD), and Photoluminescence spectroscopy (PL) methods. Morphology of nanoparticles obtained a small granular shape with an average crystallite size of 60 nm. In addition, the direct band gap was calculated using Tauc's approach. Comparing with pure ZnO, the band gap of the doped-ZnO NPs is smaller and depends on the type of dopants. Moreover, photocatalytic activity of all samples was investigated by the degradation of methyl orange (MO) dye under UV irradiation in an aqueous medium. Co-Ni-ZnO possesses excellent photocatalytic activity for the degradation of MO when compared to Co-ZnO and ZnO. In addition, the photocatalytic activity of Co-ZnO improves in the presence of nickel dopant. Moreover, the photocatalyst could be reused for four times without remarkable loss of its activity. Manuscript profile

  • Article

    2 - Optical and photocatalytic properties Undoped and Mn-doped ZnO nanoparticles synthesized by hydrothermal method: Effect of annealing temperature
    Iranian Journal of Catalysis , Issue 2 , Year , Spring 2015
    Undoped and Mn-doped ZnO nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. Structural, chemical and optical properties of the samples were studied by X-ray diffraction (XRD), Field Emission scanning elec More
    Undoped and Mn-doped ZnO nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. Structural, chemical and optical properties of the samples were studied by X-ray diffraction (XRD), Field Emission scanning electron microscopy (FESEM), UV-Vis spectrophotometry and Fourier transform infrared (FT-IR) spectroscopy. The phase purity was confirmed by X-ray powder diffraction (XRD) and XRD spectra showed that all the samples were hexagonal wurtzite structure and as the annealing temperature increases the material becomes less crystalline. In addition, the average crystal size was found to be 15-30 nm from SEM and XRD. It is seen that the optical band gap increases when the ZnO is doped with manganese and decreases when annealing temperature increases. The photoacatalytic activity of Undoped and Mn-doped ZnO nanoparticles was tested by the degradation of metyl orang (MO) under UV light and indicated that Mn-doped ZnO has higher photocatalytic activity relative to ZnO nanoparticles and photocatalytic activity decreases when annealing temperature increases. Manuscript profile

  • Article

    3 - Sonochemical synthesis of undoped and Co-doped ZnO nanostructures and investigation of optical and photocatalytic properties
    Iranian Journal of Catalysis , Issue 1 , Year , Winter 2016
    In this paper, undopedZnO and Co-ZnOnano structureswith different molar ratio of Cobalt have been synthesized by the sonochemical method. Structure have been characterized by Fourier Transform (FTIR) and UV–Vis spectroscopy,Scanning Electron Microscopy (SEM), Ener More
    In this paper, undopedZnO and Co-ZnOnano structureswith different molar ratio of Cobalt have been synthesized by the sonochemical method. Structure have been characterized by Fourier Transform (FTIR) and UV–Vis spectroscopy,Scanning Electron Microscopy (SEM), Energy Dispersive Analytical X-Ray (EDAX), and X-Ray Diffraction (XRD) methods. Moreover, the direct band gap has been calculated by Tauc’s approach.Moreover, mean crystal size has been estimated by Scherrerequaton. Furthermore, photocatalytic activity for all samples has been investigated under UV irradiation in an aqueous medium. Compared with pure ZnO, the band gap of the Co-ZnOhas been shown decrease and it is dependent on the content of dopants. Also, photocatalytic activity improves in the presence of cobalt dopant. Manuscript profile

  • Article

    4 - Incorporation of Pb2+, Fe2+ and Cd2+ ions in ZnO nanocatalyst for photocatalytic activity
    Iranian Journal of Catalysis , Issue 2 , Year , Spring 2018
    In the present study, Pb-ZnO, Fe-ZnO, Cd-ZnO and Pb-Fe-Cd-ZnO nanoparticles were synthesized by the sonochemical method and those structural and optical properties were investigated by Fourier Transform Infrared spectroscopy (FTIR), UV-Vis spectroscopy, Field Emission S More
    In the present study, Pb-ZnO, Fe-ZnO, Cd-ZnO and Pb-Fe-Cd-ZnO nanoparticles were synthesized by the sonochemical method and those structural and optical properties were investigated by Fourier Transform Infrared spectroscopy (FTIR), UV-Vis spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM) and X-Ray Diffraction (XRD). Average crystallite size obtained was 60 nm. Moreover, the direct band gap has been calculated using Tauc's approach. Compared with pure ZnO, the band gap of the doped-ZnO NPs is smaller and it depends on the type of dopants. In addition, photocatalytic activity of all samples has been investigated by the degradation of congo red (CR) dye under UV irradiation in an aqueous medium. In the presence of ZnO NPs photocatalytic degradation of 35% was obtained for 180 min. But Pb-ZnO, Fe-ZnO, Cd-ZnO and Pb-Fe-Cd-ZnO have shown the degradation of 45, 57, 65 and 80% respectively; they have the faster decolorization as compared with the ZnO NPs. Moreover, the photocatalyst could be reused for five times without remarkable loss of its activity. Manuscript profile

  • Article

    5 - مطالعه برهم‌کنش DNA تیموس گاوی با کمپلکس رنیم (I)تری‌کربونیل با لیگاند شیف‌باز دودندانه با روش‌های متفاوت طیف‌سنجی
    Journal of applied research in chemisry , Issue 2 , Year , Summer 1397
    توانایی پیوند و برهم‌کنش کمپلکس رنیم (I) تری‌کربونیل شامل لیگاند دی‌ایمینی ['N,N_بیس (بنزآلدهید)-1و2–دی ایمینواتان] و با نام اختصاری [Re]، به DNA استخراج‌شده از تیموس گوساله (CT-DNA) با روش‌های طیف‌نورسنج UV-Vis، طیف‌سنجی فلورسانس، طیف دورنگ‌نمایی دورانی (CD)، دنا More
    توانایی پیوند و برهم‌کنش کمپلکس رنیم (I) تری‌کربونیل شامل لیگاند دی‌ایمینی ['N,N_بیس (بنزآلدهید)-1و2–دی ایمینواتان] و با نام اختصاری [Re]، به DNA استخراج‌شده از تیموس گوساله (CT-DNA) با روش‌های طیف‌نورسنج UV-Vis، طیف‌سنجی فلورسانس، طیف دورنگ‌نمایی دورانی (CD)، دناتوره شدن گرمایی و ولتامتری چرخه‌ای (CV) بررسی شده است. تجزیه و تحلیل داده‌های طیفی هر کدام از این روش‌ها، به‌طور مجزا اطلاعاتی در خصوص چگونگی پیوند یادشده می‌دهد. در مجموع، از جمع داده‌های طیف‌نورسنج UV-Vis، طیف دورنگ‌نمایی دورانی CD و دناتوره شدن گرمایی، نوع و مقدار برهم‌کنش کمپلکس‌ها با DNA تعیین و تغییرهای ساختار DNA بررسی شد. (Kb) ثابت پیوند کمپلکس با DNA، با استفاده از داده‌های طیف‌نورسنج UV-Vis محاسبه شد. نتایج نشان داد که کمپلکس [Re]، نسبت به سایر کمپلکس‌های شیف‌باز، به‌طور نسبی برهم‌کنش خوبی دارند. در همه آزمایش‌ها، برهم‌کنش را از طریق جایگیری جزیی و الکتروستاتیک پیشنهاد می‌کنند. البته برهم‌کنش از طریق جایگیری غالب است، چون بیشتر آزمایش‌ها این نوع برهم‌کنش را تأیید کردند. Manuscript profile