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Document Type |
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Thesis |
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Document Title |
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Growth and Characterization of ZnO Nanorods by Hydrothermal Technique: A Systematic Study of Growth Parameters Influence نمو وتوصيف قضبان اكسيد الزنك) (ZnO النانوية بتقنية الحرارة المائية )الهيدروثرمال( : دراسة منهجية لتأثير عوامل النمو |
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Subject |
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Faculty of Science |
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Document Language |
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Arabic |
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Abstract |
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The successful synthesis of ZnO nanorods requires two steps: the deposition of ZnO seed layers on a glass substrate and the hydrothermal growth of ZnO nanorods.
Firstly, in the present work, we have investigated the effect of different variables ( zinc salt nature, concentration, time, temperature, seed layer preparation, substrate orientation) on the final morphology of ZnO nanorods obtained via hydrothermal technique has been investigated. The characterization of the samples has been carried out by Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV-Vis transmittance, and photoluminescence. We found that the growth temperature 100°C, growth time 3 h, 0.05 M precursor concentration, and 0.1 M of zinc chloride seed layer solution concentration are more favorable conditions for better orientation and excellent crystallinity of the ZnO nanorods. The results showed that all the above-mentioned variables control the shape and/or size of the synthetized ZnO nanostructures. In particular, the seed layer preparation method and the nature of the salt source plays a key role in the nanorods size. more specifically, the variation of the salt concentration influences the nanorods morphology, but the influence of the concentration depends on the used salt nature. In the case of zinc chloride, we have noticed the modification of the ZnO nanostructures, with salt concentration increase, from nanorods to simonkolleite hexagonal nanodisks. In the case of zinc nitrate, the nanostructure morphology varies from nanorods at low concentration to nanosheets at high concentration. While in the case of zinc acetate, the obtained morphology remains nanorods, but we have noticed that increasing the salt source leads to the variation in the length and the diameter of the nanorods. Additionally, it was noted that temperature and growing time had an influence on the aspect ratio. Finally, by changing the substrate orientation in the solution container during the growth of ZnO nanorods, we have discovered a simple and novel method for preparing ZnO nanotubes. This is also an important factor that controls the produced nanostructured ZnO. In the second part of this work, the photocatalysis activity of the realized nanostructures was tested in the degradation of methylene blue (MB) dye. The results indicate that the ZnO nanorods prepared at higher temperature exhibits a superior photocatalysis activity to the absence of zinc vacancy defects (Vzn) deduced from photoluminescence measurements. |
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Supervisor |
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Prof. Dr. Mohammed Salah Aida |
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Thesis Type |
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Doctorate Thesis |
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Publishing Year |
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1445 AH
2023 AD |
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Co-Supervisor |
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Dr. Ali Abdeldaim Hassnen |
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Added Date |
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Sunday, October 29, 2023 |
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