Study of polycrystalline gold surfaces by potential-dependent optical sum frequency generation

Sammanfattning: With the increase in demand for renewable energy, the comprehension of chemical processes is essential to improve the design of catalysts in order to achieve better performance. This thesis summarizes the experimental investigation of redox reactions on polycrystalline gold surfaces by combining electrochemistry with operando surface-specific sum frequency generation (SFG) for a wider anodic potential interval than previously studied in acidic aqueous medium (H3PO4, pH 1). This configuration provides new insight about the chemical processes involved in the formation and reduction of gold oxides. More precisely, the migration of oxygen below the gold surface leading to a stratified structure has been suggested for the first time. This information is relevant to bring more clarity about redox reactions on gold surface during catalytic reactions.