Figure 2.

Partial differential charge density projecting to the specific energy level. The projected density of state between the O₂ molecule on (a) Fe-SAC and (b) Fe₁Co₁-DAC. (The blue area represents the loss of electrons, and the yellow area represents the gain of electrons. The Fermi energy is set to 0 eV.) (c) The reaction free energy (at 0.9 V vs RHE) of the competing steps between single-site association and dual-site dissociation mechanisms on Fe₁Co₁-DAC, according to the constant-charge and constant-potential method. (d) The O–O bond cleavage barrier of O₂* along with hydrogenation on Fe-SAC and Fe₁Co₁-DAC. The associative pathway barrier of O₂* + H → OOH* on Fe₁Co₁-DAC. The free energies of Fe-SAC and Fe₁Co₁-DAC with no adsorption are set as references for other intermediates along the reaction (G = 0 eV).