Having ruled out paths (i) and (iv), we finally turn our attention to the competition between OOH* dissociation via the dissociative path (ii) and protonation to HOOH* via the peroxide path (iii). These two steps do not involve any type of concerted processes and are therefore rather straightforwardly sampled using single reaction coordinates. Our results on OOH* dissociation with O-O distance as the CV are shown in Fig. (a) for the same conditions of surface charging σ as above: PZC (dashed line), ca. 0.03 V vs. SHE (dashdotted line) and ca. -0.2 V vs. SHE (solid line). These one-dimensional free energy curves nicely reflect the (y-axis) picture extracted from the heatmap of Fig. . We first note the non-negligible ca. 0.2-0.3 eV effect of potential due to the local interfacial field. Despite this promotional effect at negative charging, however, the dissociation barrier is still relatively large and measures >0.5 eV even for the more reducing conditions considered (cf. exact values in the SI, Table ). In comparison, much lower barriers are predicted for OOH* protonation to HOOH* in Fig. (b). While using again the O-H coordination number ξ + as the CV, we find a stronger response to potential for this PCET step which is in line with the (x-axis) picture extracted from Fig. . As a result, the activation energy is reduced from ca.