Density functional theory investigation of the reaction mechanisms for selective oxidation of alcohols on gold catalysts

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2016

Author

Dernek, Ozan

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Most alcohols, when exposed to oxygen, are converted into CO2 and H2O as a result of a combustion reaction. Such reactions consist of several intermediate steps, which produce industrially valuable chemical species such as esters, ketones, carboxylic acids and aldehydes. These chemicals find uses in a wide range of applications in food, pharmaceutical, polymer and plating industries along with many others. As a result, there are considerable economical interests in the design of efficient, low-cost and environmentally low-impact synthetic routes of these products. Selective oxidation provides a way to interrupt the combustion reaction at the desired stage and extract the by-product of interest. The variety of these intermediate products and the particular mechanism is dictated by the environment and the catalyst used. Experimental studies have already indicated that the Au nanoparticles and Au surfaces pre-treated with atomic oxygen successfully catalyze selective oxidation. Current oxygen pretreatment techniques are, however, difficult and costly. The aim of this study is to design Au surfaces by means of doping the surface with Ni and Rh atoms in low concentrations to increase the performance of the surface for selective oxidation of ethanol. We utilize arguably the most successful theoretical method to ever have been used in surface science, namely Density Functional Theory (DFT), to understand the selective oxidation of ethanol. We present results concerning the dissociation of ethanol into subcomponents on these doped surfaces.

Subject Keywords

Density functionals., Surfaces (Physics)., Alcohols., Oxidation., Catalysts., Gold.

URI

http://etd.lib.metu.edu.tr/upload/12620409/index.pdf
https://hdl.handle.net/11511/26082

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

O. Dernek, “Density functional theory investigation of the reaction mechanisms for selective oxidation of alcohols on gold catalysts,” M.S. - Master of Science, Middle East Technical University, 2016.