Fig. 3: OER free energy profiles and microkinetic modeling results.

Grand free energy profiles at the equilibrium potential for OER on a NiOOH, b Ni(Co)OOH, and c Ni(Fe)OOH following different reaction mechanisms. d The dominant mechanism for OER on Ni-based LDHs as a function of both the catalyst composition and the applied potential (η0 = (U – 1230) mV) predicted by our microkinetic modeling scheme. The proportions of colors in the intersection at each η0 correspond to the proportions of contributions from different types of mechanisms.