الفهرس 
Chapter 1 : Introduction and Objectives of InvestigationOnly 14 pages are availabe for public view
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Abstract
Cobalt oxides (CoO1-1.5) have attracted the attention of researchers recently because the catalytic activity of one of them (Co3O4) has been shown to be comparable to the strong catalytic activity of noble metal-based catalysts in the course of oxidation of gas molecules. Carbon monoxide <CO molecules> Moreover, catalysts based on metal oxides are considered to have an industrial advantage because they are more stable and less expensive than rare metal catalysts, even if they are relatively less active. And because the <Catalyst> catalyst derives its importance from the applied importance of the catalyst reaction, it should be noted that the <CO oxidation reaction> is important because it is one of the most important means proposed to reduce carbon monoxide emissions that are harmful to the environment and health.
The research included in this thesis focused on temperature-programmed studies of the course and products of the reduction of cobalt oxides, because the oxidative-reductive catalytic activity <Redox catalysis> requires the availability of active sites based on metal ions capable of reflexive oxidation and reduction . The research was planned to achieve the following objectives:
(1) Preparation of what requires laboratory preparation from the three cobalt oxides (CoO, Co2O3, and Co3O4).
(2) Determination of the following properties of the structure of the total oxides: composition and structure, thermal stability, and redoxability, using X-ray diffraction (XRD) and infrared absorption spectroscopy. Non-in situ <Ex-situ FTIR>, thermogravimetric analysis <TGA>, and thermoprogrammed reduction <TPR> in an ocean of hydrogen molecules.
(3) characterization of the calorically programmed reduction products and steps of mixed cobalt oxide (Co3O4 = CoO.Co2O3) and the extent to which they are affected by changing the reduction parameters (heating rate <Heating rate>, reduction surroundings composition> <H2/N2, oxide sample mass <Oxide sample mass>, Gas flowrate and measurement mode (Isothermal and Nonisothermal).
(4) Identify the formations of cobalt oxides and their reduction products that are capable of reflexive oxidation and reduction, using programmed periodic measurements of the temperature of oxidation and reduction <Cyclic TPR/TPO/TPR>.
(5) Detection of the electronic properties <Electronic transfers and transitions> of cobalt oxides and their reduction products by employing UV-Vis DRS>.
(6) Nitrogen gas <N2 sorptiometry at 77 K to determine the specific surface area of the surfaces of the oxides and their reduction products.
(7) Following up the catalytic activity of the oxides and their reduction products towards the oxidation of carbon monoxide (CO + O2) to carbon dioxide (CO2) using In-situ FTIR absorption spectroscopy.
(8) Processing the results of isothermal and non-isothermic reduction, and the results of carbon monoxide oxidation measurements, to determine the molecular manifestations of catalysts, the kinetic parameters of reduction, and the specific catalytic activity towards the formation of CO2 molecules. molecules>.
(9) Prove the relationship between the catalytic activity and the properties of the oxides and their reduction products in order to clarify the role of the cobalt oxidation state in determining and developing the catalytic activity of their surfaces.
It can be summed up the most important conclusions that the studies led to the content of the thesis is that the formation of double and trivalent cobalt ions by oxygen ions of the retinal material (Co2 + - O2 - - Co3 +) enhances the thermal stability of the entire oxide material (Co3O4) as well as the catalytic activity of its surfaces, especially if it is This coincides with the reversible oxidation and reduction ability of the material.It should be noted that these ionic pairings of transition elements enhance the adsorption of oxygen molecules and electron availability and mobility, which are among the most important surface attributes of redox catalysis. catalysis) on the surfaces of solids.When the quantitative transformation of cobalt ions to the metallic state (Coo), this is coupled with a radical transformation of the surface chemistry and then of the surface attributes of the catalytic activity and its mechanism <Catalysis mechanism>.