New concepts or chemistry is an urgent requirement for rechargeable batteries to achieve a low-cost, user-friendly nature with adequate energy densities and high levels of safety.

An approach to decreasing the overpotential, increasing the stability, and optimizing the noble‐metal composition of electrocatalysts for the oxygen evolution reaction (OER) in acidic media is demonstrated. Essential components of this approach are: 1) combining an active (unstable Ru) component with a dopant (Zn)‐activated passive (stable Ti) element, 2) blending these elements by co‐electrodeposition in an acidic environment in which dissolution of the unstable component (excess Ru) promotes roughness, and 3) further increasing the roughness of the resultant electrode through chemical inhomogeneity by the incorporation of Ti and through structural inhomogeneity by incorporation of Zn in RuO2. The composition of the electrode with the maximal activity is Ru0.258Ti0.736Zn0.006Ox, and its activity is four times higher than that of RuO2. The electrochemical stability towards the OER follows the order RuTiZn>RuTi>RuZn>Ru. This design strategy provides a facile method to improve activity without compromising stability.

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Supports over which electrocatalysts are deposited play a crucial role in the oxygen evolution reaction (OER), because they influence the surface roughness, morphology, electronic structure, and conductivity of electrocatalysts. In this context, we designed a hybrid carbon support having an earth‐abundant metal as an interlayer between a Co3O4 electrocatalyst and a carbon support. The present approach resulted in an electrode that was three dimensional with high porosity, provided low resistance to parallel electron conduction pathways through the metallic interlayer, and modulated the electrocatalytic activity of Co3O4 by affecting its electronic structure. To rationalize the effect of the metal interlayer, a range of non‐noble earth‐abundant metals (e.g. Cu, Mo, Ti, Al) were explored, of which the Cu‐modified carbon support resulted in maximum specific activity (i.e. activity per electrochemical surface area) for the OER. Whereas both the electronegativity and conductivity of the metal interlayer were found to influence the OER activity, the dominant controlling factor in the explored systems was conductivity. The specific activity of the OER of electrodeposited Co3O4 was found to have a near‐linear relationship between the electrical conductivity and the electron‐donor metals (e.g. Ti, Al) and another near‐linear relationship having different intercepts with electron‐acceptor metals (e.g. Cu, Mo, W). The above understanding can be useful in increasing the OER activity of electrocatalysts through support–electrocatalyst interactions.