The most stable binding sites for the ORR intermediates on Pt10 and Pt5Ge5 deposited on the rest of the 2D materials are displayed in Figures and. The preferred adsorption mode for OOH* is end-on (η 1 ) for Pt10 supported on 585-dV, gr-B and MoS2, forming a single Pt-O bond. In silicene and germane, OOH* follows the same adsorption mode but it binds to the surface instead to Pt, while in Pt10/SmSI, it prefers the side-on (η 2 ) mode adsorbing to a Sm atom that has migrated from the surface to the top of the cluster. This is in contrast to the di-σ configuration found in phosphorene. Despite end-on and side-on presenting a somewhat less pronounced O-O activation compared to the di-σ in phosphorene, the activation is sufficient to dissociate the O-O bond spontaneously. The dissociated fragments, i.e., OH* + O* dual adsorption, are then adsorbed to vicinal atoms, Pt in 5-8-5-DV, gr-B and 2H-MoS2, and to the support in the case of silicene and germanene. In Pt10/SmSI, OH* and O* are binded precisely on the cluster-support interface to a Sm-Pt-Sm triangular unit.