The binding strength of reactive intermediates with catalytically active sites plays a crucial role in governing catalytic performance of electrocatalysts. NiFe hydroxide offers efficient oxygen evolution reaction (OER) catalysis in alkaline electrolyte, however weak binding of oxygenated intermediates on NiFe hydroxide still badly limits its catalytic activity. Now, a facile ball‐milling method was developed to enhance binding strength of NiFe hydroxide to oxygenated intermediates via generating tensile strain, which reduced the anti‐bonding filling states in the d orbital and thus facilitated oxygenated intermediates adsorption. The NiFe hydroxide with tensile strain increasing after ball‐milling exhibits an OER onset potential as low as 1.44 V (vs. reversible hydrogen electrode) and requires only a 270 mV overpotential to reach a water oxidation current density of 10 mA cm−2.

Noble metals have an irreplaceable role in catalyzing electrochemical reactions. However, large overpotential and poor long-term stability still prohibit their usage in many reactions (e.g., oxygen evolution/reduction). With regard to the low natural abundance, the improvement of their overall electrocatalytic performance (activity, selectivity, and stability) was urgently necessary. Herein, strong metal–support interaction (SMSI) was modulated through an unprecedented time-dependent mechanical milling method on Pd-loaded oxygenated TiC electrocatalysts. The encapsulation of Pd surfaces with reduced TiO2–x overlayers is precisely controlled by the mechanical milling time. This encapsulation induced a valence band restructuring and lowered the d-band center of surface Pd atoms. For hydrogen peroxide electrosynthesis through the two-electron oxygen reduction reaction (ORR), these electronic and geometric modifications resulted in optimal adsorption energies of reaction intermediates. Thus, SMSI phenomena not only enhanced electrocatalytic activity and selectivity but also created an encapsulating oxide overlayer that protected the Pd species, increasing its long-term stability. This SMSI induced by mechanical milling was also extended to other noble metal systems, showing great promise for the large-scale production of highly stable and tunable electrocatalysts.

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Exploration of the highly efficient bi‐functional catalysts toward the reduction of CO2 and decomposition of Li2CO3 at the cathode is the key for high‐performance Li‐CO2 batteries. Herein, topological defect‐rich graphene (TDG) based materials are developed as metal‐free cathodes for Li‐CO2 batteries, presenting an unprecedented full discharge capacity of over 69 000 mA h g−1 at the current density of 0.5 A g−1, a relatively small voltage gap of 1.87 V (Li/Li+) even at an extremely high current density of 2.0 A g−1, and an excellent long‐term stable cycle life of up to 600 cycles at 1.0 A g−1. The outstanding performance of Li‐CO2 batteries with the TDG cathodic electrocatalyst can be attributed to the introduction of topological defects in the carbon skeleton, providing sufficient active sites for CO2 reduction and evolution to facilitate the formation/decomposition of Li2CO3 during the discharging/charging process. The density functional theory calculations reveal the superiority of the negatively charged C atoms in topological defects as the adsorption for CO2 molecules and the activation sites for the decomposition of Li2CO3, and that the heterocyclic pentagon ring (C5) has a relatively low theoretical potential gap (1.01 V) during the charge and discharge processes.

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