Activity trends. A systematic decrease in the Gibbs free energy of hydrogen peroxide has been observed across the perovskite series from CaTiO 3 to CaFeO 3 (Fig. ). In the case of late transition metals such as cobalt (Co) and nickel (Ni), the Gibbs free energy increases as the polaronic effect diminishes. Notably, iron (Fe) with an e 1 g occupancy exhibits a Jahn-Teller polaron and 10 the lowest Gibbs free energy for this reaction. This demonstrates that the polaronic effect is the initiating factor in the evolution of hydrogen peroxide. The free energy levels of various reaction intermediates, including OH * (Fig. ), O * (Fig. ), and OOH * (Fig. ), exhibit a correlation in energy. Specifically, OH * displays a trend analogous to that of hydrogen peroxide, while both O * and OOH * demonstrate similar behavior, with the exception of Vanadium (V). These analogous trends establish a linear scaling relation between intermediates, reflecting an intrinsic relationship among intermediate binding energies, which is well-documented for catalytic surfaces of metals and metal oxides . Notably, linear correlations such as those observed between OH * and O * binding energies (where a slope of approximately 0.5 indicates the bonding difference) exemplify these scaling relationships: O * , with dual surface bonds, exhibits a stronger binding compared to OH * , which forms a single bond to the surface.