907129.fig.005
Figure 5: DFT-calculated potential-dependent reaction paths for the oxidation of methanol to CO over Pt(111) [1]. At 0.5 V, both experiments and theory point to the onset of dual paths. The primary path, available over a wide range potentials, is shown in red. It proceeds via a sequence of C–H bond activation steps ultimately forming the hydroxyl methylene intermediate (CHOH) before activating the final O–H bond to form CO. The minor path begins between 0.4–0.5 V RHE proceeds via the initial activation of O–H bond of methanol to form a surface methoxy intermediate which subsequently reacts to form formaldehyde consistent with previous speculations [122].