Engineering the Ir─O─Ni Interface Bonds in Ir@Ni‐MOF to Accelerate Li 2 O 2 Formation and Decomposition for High‐Reversibility Li‐O 2 Batteries

Abstract

ABSTRACT Aprotic lithium‐oxygen (Li‐O 2 ) batteries have attracted considerable interest due to their ultrahigh theoretical energy density, yet their practical application is severely limited by slow cathode reaction kinetics and large voltage hysteresis. Here, we report an interface engineering strategy to construct ultrafine Ir nanoparticles anchored on Ni‐based metal‐organic framework (Ir@Ni‐MOF) as an efficient bifunctional cathode catalyst for Li‐O 2 batteries. Experimental and theoretical calculations reveal the formation of interfacial Ir─O─Ni chemical bonds, inducing significant charge redistribution and downshifting the d‐band center of Ir@Ni‐MOF. This electronic modulation weakens the adsorption affinity toward the LiO 2 intermediate, thereby enhancing a solution‐mediated discharge pathway to form nanosheet‐like Li 2 O 2 with intimate interface contact and rapid charge/mass transfer, which facilitates reversible decomposition during charging. As a result, the Ir@Ni‐MOF cathode delivers a remarkably low overpotential of 0.76 V, an extended cycling stability over 400 cycles at 500 mA g −1 , outperforming most reported MOF‐based and noble‐metal catalysts. This work provides a promising avenue for designing high‐performance Li‐O 2 batteries and beyond through precise electronic structure engineering.