The Synthesis And Study On Photo-thermal Catalytic Properties Of Nickel Ferrite Catalysts

With higher concentrations of CO2 were led by human activities in the atmosphere, the greenhouse effect has had a serious impact on the environment. It was a hot topic to find some ways to address the problem of CO2 pollution in the world. It was a method of highly viable and easy to implement to convert CO2 to hydrocarbons by catalysts in the photochemical conditions. This method not only can reduce the CO2 content in the atmosphere to solve the problem of environmental pollution, and its reaction products can alleviate the problem of resource shortage at present in order to the chemical fuels of simple storage. Ferrite materials become a one of the most important materials thanks to low price and simple preparation process in the field of CO2 catalytic reduction. Therefore, this paper focuses on the nickel ferrite with best performance, using a variety of methods to modify it, and strives to get the ultimate catalytic performance of the new catalytic materials. Detailed research work and the results of the following three parts:1. The Synthesis and Study on Photo-thermal Catalytic Properties of Nickel Ferrite Catalysts with High Concentration Oxygen Vacancies.Using the solvothermal method and ethylene glycol as the surfactant, the oxygen vacancy content of the nickel ferrite catalyst was adjusted by different ethylene glycol ratio in the precursor solvent. The intrinsic relationship between the concentration of oxygen vacancy in the catalyst and the photocatalytic efficiency was investigated. The mechanism of the thermal catalytic reaction of nickel ferrite with oxygen-deficient and the effect of the surfactant on the crystal structure of the catalyst were studied by solvothermal synthesis of the catalyst. Ferrite with oxygen vacancies has the ability to splitting carbon dioxide and water, and has the advantages of simple preparation process and low cost of raw materials. The high concentration of oxygen vacancies in the nickel ferrite samples lead to the enhancement of visible light absorption capability. Not only is the role of oxygen as a trap center, but also the high concentration of oxygen vacancy creates an impurity level near the valence band and induces the band gap narrowing. Therefore, this paper main content is to the research and development of new nickel ferrite in the synthesis process, and explore the method of more convenient synthesis of nickel ferrite with high density oxygen vacancy.2. The Synthesis and Study on Photo-thermal Catalytic Properties of Nickel Ferrite Catalysts with Different Crystal face and Morphology.Nickel Ferrite catalysts with different morphologies and expose different crystal faces were selectively prepared by different reaction methods and reaction solvents. The catalytic effect of Nickel Ferrite with different crystal faces was investigated because the surface structure of same compound was different thanks to the exposed markedly different crystal face.The exposed crystal face of the catalyst is directly contacted with the reaction component. For the catalyst, the more the high-energy active crystal face was exposed, the better the catalytic activity of the catalyst. We can selectively adjust the high energy active surface and improve the performance of catalysts by a guide agent, a surfactant. Therefore, this paper main content is to the research and development of new nickel ferrite in the synthesis process, and explore the method of more convenient synthesis of nickel ferrite with high energy active crystal face.3. The Synthesis and Study on Photo-thermal Catalytic Properties of Nickel Ferrite Catalysts with 3DOM structure.Different size PMMA as template and the Nickel salt and iron salt dissolved in a certain proportion ethylene glycol and methanol solution as the precursor to synthesize catalyst with different pore sizes 3DOM structure. The relationship between different pore structure of catalyst and reaction efficiency was researched. And the relationship between different pore structure of catalyst and specific surface area was researched. The catalyst with 3DOM structure and high surface has been hot research field 3DOM structure of the porous metal oxide catalyst with high specific surface area can help to improve the catalytic reaction efficiency. And because of its periodic arrangement of the pores, it is possible that the catalyst has a photonic crystal-specific effect, called photonic bandgap (prevents light at a particular wavelength, that is to say, the residence extension of time of the light in the catalyst). The specific structure improve the absorbance of catalyst, and ultimately improve the material’s thermal and photo performance.Therefore, this paper main content is to the research and development of new 3DOM nickel ferrite in the synthesis process, and explore the method of more convenient synthesis of 3DOM structure nickel ferrite with different pore size.