الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Our thesis is divided into four chapters. It focuses on the preparation of Ag NPs/reduced (Ag-RGO) and Au NPs/reduced (Au-RGO) nano-composites with different Ag and Au NPs loading ratios, characterization and investigation of subsequent utilization of the prepared materials with optimum Ag and Au NPs loading ratios for lead (II) and zinc (II) heavy metals ions removal from aqueous solution. Briefly:
Chapter 1: The introduction is a general overview on graphene and grapheme nanocomposite, preparation, characterization and potential applications.
Chapter 2: Literature review of this research work includes the fundamentals and purpose for choosing (Ag-RGO) and (Au-RGO) nanocomposites, the interesting and improved features of as-synthesized Ag-RGO and Au-RGO nanocomposites and the proposed fabrication route for silver and gold nanoparticles decorated reduced graphene oxide composites. Finally, the chapter will end up with discussing the performance of nanocomposites in wastewater treatment from heavy metal ions.
Chapter 3: Materials and methodologies, introduced the reliable pathway for preparation of GO and Ag-RGO and Au-RGO nanocomposites. Various characterization tools that employed to define the nanocomposites characteristics such as X-ray diffraction (XRD), High resolution transmission electron microscope (HR-TEM), Energy-dispersive X-ray spectroscopy (EDX), Dispersive Raman spectrometer, N2 adsorption-desorption isotherm measurements and UV-Vis Spectrophotometer. At last, the measurements of heavy metal ions removal from aqueous solutions using the obtained Ag-RGO and Au-RGO are described. Atomic Absorption Spectrophotometer (AAS), was used for measuring the residual concentrations of Zn(II) and Pb(II) metals.
Chapter 4: Results and Discussion
This chapter explores the result obtained from analytical techniques for the characterization studies of structural, morphological features of Ag-RGO and Au-RGO nanocomposites. In addition, the performance of Ag-RGO and Au-RGO nanocomposites as superior sorbents for heavy metal ions also was investigated.
The optimum Ag loading ratio for effective removal Zn2+ andPb2+ metal ions was 20 wt% Ag-RGO and 30 wt% Ag-RGO respectively. While the optimum Au loading ratio was 10 wt% Au-RGO and 20 wt% Au-RGO for removal of Zn2 and Pb2+ metal ions respectively.
It is clear that the percentage metal ions removal approached equilibrium within 3hrs using Ag-RGO recording 78% Zn (II) removal and 99.4% Pb (II) removal efficiency. While equilibrium time reduced to 50 min using Au-RGO recording 86% Zn (II) and 99.7% Pb (II) removal efficiency.
Moreover, Using Au NPs decorated RGO can reduce the loading ratio of NPs in RGO nanocomposite and save the time for operating the experiments from 3 hrs to only 50 min.
These results may be attributed to the highest surface area of Au NPs in comparison with AgNPs.