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Document Type |
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Thesis |
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Document Title |
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SYNTHESIS OF METAL NANO-PARTICLES, THEIR PROPERTIES, AND TECHNOLOGICAL APPLICATIONS تحضير جزيئات النانو المعدنية ودراسة خصائصها وتطبيقاتها التكنولوجية |
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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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In this dissertation sodium dodecyl sulfate (SDS) capped- Cu nanorods were prepared by using ascorbic acid under light emitting diode (LED) irradiation for the first time. The preliminary indications of CuNPs production were the appearance of yellow (Cu2O) and red-chocolate color (Cu⁰) in absence and presence of LED exposure at room temperature. The optical, spectroscopic and morphological properties of as-prepared NPs were characterized using UV-visible spectroscopy through the presence of a characteristic surface Plasmon resonance (SPR) band for Cu⁰ at 584 nm along with high absorbance at 800 nm for Cu2O. X-ray diffraction (XRD) shows that the red-chocolate color consist of 90% metallic Cu⁰ and 9.7% Cu2O with face cubic center unit cell structure of CuNPs. Transmission electron microscope (TEM), energy dispersive X-ray (EDX), and scanning electron microscope (SEM) revealed that the CuNPs were nano-rods with an average length ranging from 300 to 350 nm. LED light assisted degradation of trypan blue (TB) was also investigated in presence of CuNPs and K2S2O8. The existence of sulfate radicals (SO4-•) and hydroxly radicals (HO•) generated during the degradation were identified by using different radical scavengers. Degradation follows first-order kinetics with respect to K2S2O8 concentrations. The oxidative dissolution of CuNPs was also observed along with the TB degradation. Based on the absorbance changes at 590 nm, the degradation and dissolution mechanisms were proposed and discussed.
Moreover, Degradation of trypan blue (TB) by persulfate/CuNPs system was investigated as a function of TB concentration, persulfate concentration, CuNPs concentration, pH, and reaction temperature in aqueous solution. The rate of the decolorization and destruction of aromatic ring were studied spectrophotometrically. The dye mineralization was performed with potassium dichromate for the determination of chemical oxygen demand (COD) in solution. The blue color reaction mixture became red-chocolate, purple, light blue to dark blue as a function of time. The CuNPs acted as an activator of K2S2O8 and generates various reactive oxygen and/or sulphur species. Decolorization of dye starts due to the cleavage of azo bond by the generated radical species. The role of sulfate radicals (SO4•-), and hydroxyl radicals (HO•) were established by using different radical scavengers. Degradation and mineralization of dye follows first-order kinetics. These results can support the design of remediation processes and also assist in predict their fate in environment. |
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Supervisor |
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Prof. Dr: Zaheer Khan |
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Thesis Type |
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Doctorate Thesis |
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Publishing Year |
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1444 AH
2023 AD |
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Co-Supervisor |
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Prof. Dr: Shaeel Al-Thabaiti |
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Added Date |
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Monday, July 3, 2023 |
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Researchers
| عبير حماد الجدعاني | Aljadaani, Abeer Hammad | Researcher | Doctorate | |
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