Dissociative chemisorption is an important reaction step in many catalytic reactions. An example of such a reaction is the Haber-Bosch process, which is used commercially to produce ammonia... Show more Dissociative chemisorption is an important reaction step in many catalytic reactions. An example of such a reaction is the Haber-Bosch process, which is used commercially to produce ammonia, an important starting material in the production of fertilisers. In theoretical descriptions of such chemical processes often approximations need to be made in order to keep the computational cost feasible, such as fixing the surface atoms in place, rather than allowing them to vibrate. In this work, several example systems (hydrogen dissociation on different metal surfaces) are used in order to test to what extent such approximations work well. Show less
In this thesis, the formation of hexagonal boron nitride (h-BN) __nanomesh__ structures and of graphene on Rhodium (111) is studied experimentally. The structures of h-BN and graphene are extremely... Show moreIn this thesis, the formation of hexagonal boron nitride (h-BN) __nanomesh__ structures and of graphene on Rhodium (111) is studied experimentally. The structures of h-BN and graphene are extremely similar: both of them are single atomic layers with a honeycomb lattice, and the lattice constants are nearly identical. Both materials introduce novel properties and have the potential for a variety of applications. In this thesis, the layers were grown by chemical vapor deposition (CVD) on Rh(111). During growth, the formation processes were tracked by scanning tunneling microscopy (STM). This was performed in situ, namely during deposition at the elevated temperatures, required for the growth. In this way, we have obtained detailed knowledge of the formation mechanisms. In this thesis, basic surface science principles are employed to explain the observed, special growth behavior. Our understanding of the mechanisms at play has enabled us to compose new, improved deposition recipes that result in higher quality nanomesh and graphene layers. This knowledge is not only valuable for these specific systems, but it also deepens our general insights into deposition and growth of atomically thin layers. Show less
