الفهرس 
Aim of the workOnly 14 pages are availabe for public view
 |  | from | 153 |  |  |
| | | from | 153 | | |
Abstract
English summary
This thesis consists of three main chapters
Chapter 1: Introduction
The first chapter comprises the introduction in which an outline on the definition of nanomaterials, their synthesis techniques and their applications in different fields are presented. This chapter also includes a literature survey on the previous work performed on the simple nanosized particles along with those performed on the mixed nanosized particles and their different applications.
Chapter 2: The experimental
This chapter includes a complete description of the materials, reagents, equipment and the methods used for the preparation of nanosized zinc selenide, zinc oxide, cadmium selenide and cadmium oxide by hydrothermal and co-precipitation method and some their mixed nanosized particles.
(1) Nanosized ZnSe particles were prepared by hydrothermal treatment of zinc acetate dihydrate, selenide, hydrazine, and sodium hydroxide at 100 oC for 1 h., then nanosized ZnSe was prepared by drying the as prepared ZnSe.
(2) Nanosized CdSe particles were prepared by hydrothermal treatment of cadmium acetate dihydrate, selenide, hydrazine, and sodium hydroxide at 100 oC for 1 h., then nanosized CdSe was prepared by drying the as prepared CdSe.
(3) Nanosized ZnO particles were prepared by precipitation treatment of zinc acetate, and sodium hydroxide at 100 oC for 1 h., then nanosized ZnO was prepared by drying the as prepared ZnO.
(4) Nanosized CdO particles were prepared by precipitation treatment of cadmium acetate, poly ethylene glycol 6000, and sodium hydroxide at 100 oC for 1 h., then nanosized CdO was prepared by drying at 60 °C overnight and then calcination of the as prepared CdO at 400 °C for 1 h.
In addition to description of the structure and characteristics of the used dye, Malachalite green dye (MG)), the photocatalytic process and the different parameters affecting on the photodegradation process are included in visible light.
Chapter 3: Results and discussion
This chapter contains the discussion of the results obtained and their characterization. It consists of three main parts:
Part 1 describes the characterization of the as-prepared nanosized ZnSe and ZnO as follows:
Hydrothermal reactions of zinc acetate dihydrate, selenide and sodium hydroxide in the presence of hydrazine have been investigated in order to prepare pure zinc selenide at the optimal conditions: Zn2+:Se molar ratio of 1:1, 1 h reaction time, and 100 ºC reaction temperature. And zinc oxide was prepared by using precipitation method using zinc acetate and sodium hydroxide. The estimated average crystallite size of the synthesized ZnSe nanomaterial was found to be ca. 3.42 and 27.33 nm for ZnSe and ZnO, respectively. The as-fabricated ZnSe and ZnO nanoparticles were identified using various techniques such as XRD, SEM, HR-TEM, and FT-IR.
Part 2 describes the characterization of the as-prepared nanosized CdSe and CdO as follows:
Hydrothermal reactions of cadmium acetate, selenide and sodium hydroxide in the presence of hydrazine have been investigated in order to prepare pure cadmium selenide at the optimal conditions: Cd2+:Se molar ratio of 1:1, 1 h reaction time, and 100 ºC reaction temperature. And cadmium oxide was prepared by precipitation of cadmium acetate using sodium hydroxide in the presence of poly ethylene glycol. The estimated average crystallite size of the synthesized nanomaterials found to be ca. 3.83 and 16.50 nm for CdSe and CdO, respectively. The as-fabricated CdSe and CdO nanoparticles were identified using various techniques such as XRD, SEM, HR-TEM, and FT-IR.
Part 3 Photodegradation and kinetic study of Malachalite green (MG) dyes on ZnSe, ZnO, CdSe and CdO nanoparticles.
This part deal with the results and discussion of the factors affecting the photodegradation process of the dyes from their aqueous solutions on the nanosized ZnSe, ZnO, CdSe and CdO, and the following remarks were obtained:
1- For all the nano-as-prepared samples Dye % removal decrease with increasing the initial concentration of the dye under the photodegradation process.
2- MG dye % removal increase with increasing the dose gram of ZnSe, ZnO, CdSe and CdO under the photodegradation process.
3- MG dye % removal increase with increasing basicity of the dye solution under the photodegradation process.