Atomistic Insights into Photocatalytic Mechanisms: Modeling Selected Processes with Density Functional Theory

Rising global energy demand and the environmental impact of fossil fuels have increased the need for sustainable energy solutions. Photocatalysis offers a way to harness solar energy to produce renewable fuels and industrially viable chemicals, and to degrade organic pollutants. This thesis explores the use of atomistic modeling based on Density Functional Theory to systematically model, understand, and optimize various photocatalytic processes. The research is focused on three studies: The influence of oxygen vacancies on the water oxidation mechanism on bismuth vanadate, showing that the removal of vacancies shifts the selectivity from oxygen to hydrogen peroxide; the mechanism of photocatalytic oxazolidinone oxidation to oxazolidinedione on carbon nitride, demonstrating the necessity of proton-coupled electron transfer from the substrate to the catalyst, enabled by light absorption; and photothermal carbon dioxide hydrogenation to carbon monoxide on cobalt-doped hydroxyapatite, showing that increasing the doping level changes the mechanism and nature of photoabsorption from intragap-state-induced to localized-surface-plasmon-resonance-induced. These results reveal a complex interplay between catalyst structure, nature of light absorption, and reaction mechanism, and provide valuable insights for the design of more efficient photocatalysts.

If you would like to follow the ceremony on Zoom, please, register here