Fundamental understanding of molecular reactions on metal surfaces is important for improving heterogeneous catalysis. Therefore, the reaction of small molecules on well-defined metal surfaces is... Show moreFundamental understanding of molecular reactions on metal surfaces is important for improving heterogeneous catalysis. Therefore, the reaction of small molecules on well-defined metal surfaces is investigated with state-of-the-art DFT calculations. Efforts are made to improve the agreement between experiment and theory by employing density functionals belonging to a higher level of theory than typically used. Furthermore, molecular dynamics are performed both with ab initio calculations and precomputed potential energy surfaces to investigate reaction mechanisms. This way dynamical aspects of reaction mechanisms can be investigated, e.g., the effect of rovibrational excitation of a molecule on the reaction probability and mechanism. Show less
As a virtually inexhaustible source, solar energy plays a major role in future global energy scenarios. Solar-driven water splitting via dye-sensitized photoelectrochemical (DS-PEC) devices is a... Show moreAs a virtually inexhaustible source, solar energy plays a major role in future global energy scenarios. Solar-driven water splitting via dye-sensitized photoelectrochemical (DS-PEC) devices is a scalable, affordable and sustainable technology of great potential for direct conversion of solar energy into storable chemical fuels to produce clean, cost-efficient and environmentally friendly H2 or CO2-derived fuels and thus to contribute to the transformation of a sustainable society from the blueprint to reality. Proton-coupled electron transfer (PCET) plays a crucial role in a wide range of biological and chemical reactions concerning energy conversion processes, such as natural and artificial photosynthesis. Given that the overall catalytic water oxidation consists of four consecutive PCET steps, sequential or concerted, it is therefore of fundamental significance to unveil the intrinsic catalytic mechanism as well as the factors determining the PCET rate and thus to find strategies to facilitate the catalytic water oxidation. Computational tools provide a powerful and essential technique for the understanding and engineering of efficient DS-PEC devices for water splitting. This thesis provides an in-depth understanding of the catalytic mechanisms for the water oxidation half-reaction in catalyst-dye supramolecular complexes and rational strategies to facilitate the involved catalytic reactions. Show less
