Methanol Oxidation on Pt(111) from First-Principles in Heterogeneous and Electrocatalysis

The catalytic oxidation of methanol on Pt(111) has been addressed based on first-principles electronic structure calculations. The chemical environment corresponding to the conditions in heterogeneous and electrocatalysis has been taken into account in a grand-canonical approach. Furthermore, the aqueous electrolyte in electrocatalysis has been described in an implicit solvent model. Thus, we find characteristic differences between the methanol oxidation paths in heterogeneous and electrocatalysis. The presence of the aqueous electrolyte stabilizes reaction intermediates containing hydrophilic groups thus also influencing the selectivity in the methanol oxidation. In addition, adsorbed hydrogen on Pt(111) is shown to render the electro-oxidation of methanol less efficient.