Unifying Scaling Relations and Multiple Reaction Mechanisms for Screening Transition Metal-Doped Co₃O₄ for Oxygen...

Accelerating the discovery of oxygen-evolution reaction (OER) catalysts requires high-throughput screening strategies combining descriptor-based frameworks with dedicated mechanistic analyses. In this study, we present a unified methodology using the example of doped Co₃O₄ in the OER by developing a mechanistically resolved, potential-dependent volcano approach that accounts for the uncertainty of adsorption free energies when analyzing activity trends. We evaluate the influence of different dopants (Cr, Mn, Fe, Ni, Cu, and V) on the OER activity by selectively substituting octahedral Co sites on the (001) facet of Co₃O₄ using density functional theory calculations (DFT). We identify Cr, Fe, Ni, and V as promising dopants as they exhibit increased OER activity compared to undoped Co₃O₄, while Cr shows the strongest promoting effect among all dopants considered in this study. We compare our theoretical predictions with two different series of synthesized Co₃O₄ nanoparticle catalysts and find good agreement regarding the qualitative trends of OER activity. To validate the strong promoting effect of Cr, we synthesize surface-enriched, Cr-doped Co₃O₄ nanoparticles, which confirms the theoretical prediction of increased OER activity. The theoretical model developed in this work is a transferable framework that can be equally applied to other materials and electrocatalytic processes for quantifying dopant effects by considering uncertainty and promoting effects when analyzing activity trends.