Today, the energy sector is highly dependent on heterogeneous catalysis because a future solution to end our dependency on natural sources lies in generating hydrogen by splitting water. Several... Show moreToday, the energy sector is highly dependent on heterogeneous catalysis because a future solution to end our dependency on natural sources lies in generating hydrogen by splitting water. Several transition metals, such as Pt, are known to be good catalyst materials for water splitting reactions. They play a key role in understanding the fundamental aspects of the elementary interactions occurring on the surfaces of catalysts. These surfaces, however, are generally very complex and contain a wide distribution of structurally and chemically different sites with different activities. One of the key issues in optimizing the activity of the catalysts is to distinguish and specify the active sites on the surface. In this thesis we use highly corrugated Pt surfaces and UHV techniques (TPD, LEED, and STM) to explore the effects of surface defects on adsorption and desorption of water and related adsorbates. We elucidate to what extent the substrate type influences the structure of interfacial water both in the monolayer and thin film regime. Our studies also show that step geometry is the determining factor in low temperature oxygen dissociation. Show less
As nickel and platinum are in the same group of the periodic table, the Ni(111) and Pt(111) surfaces may be expected to show similar interaction with water and hydrogen. However in this thesis, we... Show moreAs nickel and platinum are in the same group of the periodic table, the Ni(111) and Pt(111) surfaces may be expected to show similar interaction with water and hydrogen. However in this thesis, we show these interactions for Ni(111) are quite different from those of Pt(111). Moreover, our results show that the Ni(111) surface is a unique surface with regards to its chemistry of water and hydrogen. Show less
