فهرس المقالات ZnO nanostructure

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  1 - Rapid growth of zinc oxide nanobars in presence of electric field by physical vapor deposition
  Mehraban Jouya Fahime Taromian Simin Siami
  10.1007/s40094-017-0270-z
  AbstractIn this contribution, electric field has some effects to increase growth for specific time duration on zinc oxide (ZnO) nanobars. First, the zinc (Zn) thin film has been prepared by 235,000 V/m electric field assisted physical vapor deposition (PVD) at vacuum of أکثر

  AbstractIn this contribution, electric field has some effects to increase growth for specific time duration on zinc oxide (ZnO) nanobars. First, the zinc (Zn) thin film has been prepared by 235,000 V/m electric field assisted physical vapor deposition (PVD) at vacuum of 1.33 × 10−5 mbar. Second, strong electric field of 134,000 V/m has been used in ambient for growing ZnO nanobars in term of the time include 2.5 and 10 h. The performances of the ZnO nanostructure in absence and presence of electric field have been determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results of XRD analysis showed that ZnO has a hexagonal bars structure and a strongly preferred (101) orientation which is strongest than without applying electric field. SEM analysis revealed that physical vapored ZnO thin film in presence of electric field are densely packed with uniform morphological, thinner and denser in distribution. Electric field effect for ZnO growth in 2.5 h is better than it in the 2.5 h without electric field but by passing the time the media influence has good power almost as same as electric field. Through this electric field in PVD, the compact and uniform Zn film has been achieved which is less diameter than ordinary PVD method. Finally, we carry out a series of experiments to grow different-orientation ZnO nanobars with less than 100 nm in diameter, which are the time saving process in base of PVD ever reported. Therefore, the significant conclusion in usage electric field is reducing time of growth. تفاصيل المقالة
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  2 - Preparation, Characterization and Photocatalytic Activity of Ag-Cd-ZnO and Ag-Cu-ZnO Nanostructures
  Bahar Khodadadi Maryam Bordbar Maryam Sajedi
  In this study, ZnO nanopowders and ZnO doped with metals (Cu , Ag- doped ZnO) and (Cd, Ag- doped ZnO) were synthesized by the sol-gel method in order to investigation on the codoping effect on the band gap and photocatalytic activity of ZnO. The synthesized samples are أکثر

  In this study, ZnO nanopowders and ZnO doped with metals (Cu , Ag- doped ZnO) and (Cd, Ag- doped ZnO) were synthesized by the sol-gel method in order to investigation on the codoping effect on the band gap and photocatalytic activity of ZnO. The synthesized samples are characterized by IR spectroscopy technique. Moreover, the absorption coefficients of the ZnO, Ag-Cd-ZnO and Ag-Cu-ZnO were analyzed by Tauc’s approach and the direct band gap is calculated. According to these results, compared with pure ZnO, the band gap of the Ag-Cd-ZnO and Ag-Cu-ZnO decreases and it is dependent on the content of dopands. Furthermore, photocatalytic activity for all samples was investigated under UV irradiation in an aqueous medium. The results have been revealed that Ag-Cd-ZnO and Ag-Cu-ZnO shown more photocatalytic actitivity in comparison with pure ZnO. تفاصيل المقالة
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  3 - Sonochemical synthesis of undoped and Co-doped ZnO nanostructures and investigation of optical and photocatalytic properties
  Bahar Khodadadi Maryam Bordbar
  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 أکثر

  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. تفاصيل المقالة