fig4
Figure 4. DFT studies of catalytic activity among different surface metal sites. (A) Atomic arrangement of 3-CoOOH-FeD-CoV-Fe and the corresponding OER reaction pathway; (B) The Gibbs free energies for OH*, O*, and OOH* at CoOOH-Co sites, CoOOH-FeD-Fe sites, 2-CoOOH-CoV-Co1 sites, 3-CoOOH-FeD-CoV-Fe sites; (C) Calculated partial density of states (PDOS) for CoOOH-Co sites, CoOOH-FeD-Fe sites, 2-CoOOH-CoV-Co1 sites, 3-CoOOH-FeD-CoV-Fe sites; (D) Contour plot of theoretical overpotential versus ΔGOOH*-ΔGO* and ΔGOH*, highlighting the near-ideal model achieved by Fe doping and Co vacancy. DFT: Density functional theory; OER: oxygen evolution reaction.
