Figure 10: DFT-calculated potential energy surface for the catalytic oxidation of ethanol to acetic acid over Au(111) in the presence of base (OH) and in water. Both the OH as well as the metal are involved in the mechanism. In order establish an overall cycle, O2 is reduced via the electrons that from as a result of the oxidation of the alcohol as well as by the reaction protons that form upon the activation of water. Red lines refer to transition states, whereas the black lines refer to reaction intermediates.