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Developing advanced electrocatalysts is crucial for alkaline hydrogen evolution reaction (HER). A balance in adsorption energy for each reaction intermediate on the catalyst determines the overall catalytic rate. This balance is closely linked to the d‐band center, which is, in turn, controlled by the electronic structure of the active sites. Herein, C60 molecules with electron‐withdrawing properties and manganese (Mn) atoms with electron‐donating properties to drive charge redistribution on Ru active sites are strategically utilized. The synergistic and complementary effects of C60 and Mn regulate the d‐band centers of Ru sites to an optimal position, optimizing both the water adsorption and hydrogen desorption of the synthesized Ru catalysts. The constructed MnRu/C60‐3 catalyst exhibits a low overpotential of 8 mV at 10 mA cm−2, a large TOF value of 15.5 s−1, and a high mass activity of 2.39 A mg−1Ru at an overpotential of 100 mV in 1.0 m KOH. The anion exchange membrane water electrolyzer, assembled with MnRu/C60‐3 as the cathode, demonstrates excellent water electrolysis performance and high stability under industrial operational conditions. This work offers a fresh perspective on catalyst design principles by manipulating the d‐band centers of active sites using two complementary components. [ABSTRACT FROM AUTHOR]

Selecting suitable electrode materials for sodium‐ion batteries (SIBs) often relies on the experience gained from lithium‐ion batteries (LIBs), particularly in terms of thermodynamics. However, this approach may fall into a stagnant situation where the development of SIBs consistently lags behind that of LIBs due to the larger ionic radius of Na+. Accordingly, it is crucial to establish a dedicated selection rule specifically tailored for SIB electrodes to overcome this challenge. Herein, a screening method is proposed for SIB materials, where an ideal candidate shall form a stable intermediate transition phase with Na+. This phase acts as an important bridge that can regulate the insertion/extraction of charge carriers. Atomically resolved transmission electron microscopy demonstrates that KCu7S4 can react with Na+ to form a stable intermediate phase (Na3Cu4S4). Na3Cu4S4 can undergo reversible conversion reactions, contribute capacity, stabilize the tunnel structure and enhance the migration/diffusion of Na+. In contrast, Li+ can't form a stable intermediate phase in KCu7S4 during lithiation/delithiation, thus losing the ability to effectively regulate Li+ insertion/extraction. These findings provide valuable insights for the development of suitable electrode materials for SIBs, emphasizing the importance of stable intermediate phases in regulating charge carrier insertion/extraction and improving overall battery performance. [ABSTRACT FROM AUTHOR]