Oxygen evolution reaction (OER), limited by high overpotential and sluggish kinetics, represents a major bottleneck for electrochemical water splitting toward green hydrogen production. Constructing asymmetric A–O–B motifs to modulate the electronic density of states near the Fermi level through orbital coupling is crucial for optimizing the surface chemisorption properties of transition metals, thereby enabling the development of electrocatalysts with high intrinsic activity and stability. In this article, an IrO x nanocluster‐coupled Fe/Eu co‐doped nickel telluride composite catalyst (IrO x /FeEu‐NiTe x ) with ultralow Eu (0.72 at%) and Ir (0.14 at%) content was synthesized using an in situ hydrothermal method followed by an electrochemical deposition strategy. Benefiting from the design of an asymmetric dual‐electron‐bridge structure with gradient orbital coupling (Ni 3d–O 2p–Eu 4f, Ni 3d–O 2p–Ir 5d), the electronic structure of the catalyst is effectively modulated, thereby enabling the optimization of adsorption behaviors for reaction intermediates. Consequently, the optimized IrO x /FeEu‐NiTe x electrode exhibits superior OER performance, delivering low overpotentials of 205 and 334 mV at current densities of 10 mA cm −2 and 500 mA cm −2 , respectively. Furthermore, it maintains long‐term stability for over 1000 h at high current densities of 500 and 1000 mA cm −2 . When integrated into an alkaline water electrolyzer, the system achieves a current density of 500 mA cm −2 at a cell voltage of 1.64 V and demonstrates stable operation for over 1000 h. This study successfully develops a high‐performance rare‐earth‐based OER catalyst by constructing an asymmetric dual‐electron‐bridge structure with gradient orbital coupling, providing new insights into electronic structure engineering strategies.
Wu et al. (Thu,) studied this question.