Abstract
A very large number of chemical reactions take place every day in chemical industries for the production of a wide range of products, which are essential to our life, comfort, and survive. Catalysts are essential parts in chemical reactions because they allow to increase the speed of reactions by lowering the energy barrier separating reactants from products. In this context, a major problem for the commercial use of ethanol in fuel cells, which have better efficiency than combustion engines, is the development of better catalysts, which are efficient, stable, and low cost of production forproduction of hydrogen using ethanol. In recent years, a large number of experimental studies have suggested that nanoparticles (NPs) oftransition metals can contribute significantly to the development of nanocatalysts due to high reactivity observed in NPs in comparison to macroscopic particles, and mainly due to the possibility of combining two or more chemical elements in a single particle or through the alteration of the geometric particle which can contribute to increasing the reactivity. Experimental results have shown that NPs can be used also in applications in medicine, opening the possibility for new treatments andeficienia of improving existing treatments. Therefore, there is great interest in understanding what physical and chemical parameters (size,geometry, chemical composition, thermodynamic stability, reactivity, etc.) determine the success or failure of a nanocatalyst. Several studies have been conducted, however, our understanding of the atomistic thermodynamic stability of metal NPstransition is far from ideal due to the few existing studies. In this master's project, we are interested to contribute to the advancementthe study of the thermodynamic stability of transition metal NPs (Pt, Rh, Pd, etc). To achieve these goals, we will study theThermodynamic properties of NPs as a function of temperature, chemical composition, size, shape and geometric, using computer simulations based on the Monte Carlo method and empirical potentials (Quantum Sutton-Chen) and first-principles potencial based on density functional theory implemented in code FHI-AIMS).
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