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Abstract

Currently, scientists seek energy conversion options that are both environmentally and economically sustainable. A promising option is the use of transition-metal containing layered double hydroxides (LDH) as catalyst precursors. In addition, employing a combination of two metals in a bimetallic system can improve the catalyst’s properties compared to monometallic materials. The nickel and copper bimetallic systems are interesting combinations for catalyst applications. However, there are still open research questions due to contradictory results. Some previous research has reported a miscibility gap for thin films of Ni-Cu; a point where the two elements do not form an alloy or solid solution that is often omitted within investigations of supported nanoalloys. In addition, more research is needed to understand the structure-function relationship of Ni-Cu bimetallic catalysts derived from LDH precursors. The aim of this thesis was to study the Ni-Cu bimetallic catalysts using materials derived LDH precursor. Through chemical electron microscopy as a primary characterization technique, combined with complementary techniques (thermogravimetric analysis, temperature-programmed reduction, X-ray diffraction, X-ray photoelectron spectroscopy, near edge X-ray adsorption fine structure, among others), we unraveled the properties of the materials after synthesis, activation, and catalytic testing. The catalytic evaluation entailed two paragon examples of current importance: carbon dioxide hydrogenation and ammonia decomposition reactions. In addition, owing to the significance of transmission electron microscopy (TEM) analysis in this thesis and the potential damage during electron-matter interaction, a systematic analysis of beam damage in the TEM was conducted for the first time for this LDH system. The analysis describes the structural changes resulting from electron beam irradiation on LDH and derived materials.