Boosting OER Performance of NiFe‐MOFs via Heterostructure Engineering: Promoted Phase Transformation and Self‐optimized Dynamic Interface Electron Structure

Abstract How to manipulate heterostructure engineering to achieve high‐efficiency oxygen evolution reaction (OER) remains a significant challenge. Herein, a promising OER heterostructure electrocatalyst with IrNi nanoalloys (≈3.29 ± 0.12 nm) anchored on NiFe‐MOFs (IrNi@NiFe‐MOFs), exhibiting promoted phase transformation and self‐optimized dynamic interface electronic structure, via a one‐step hydrothermal method is designed and developed. Specifically, IrNi@NiFe‐MOFs displays excellent OER performance with a low overpotential of 228 mV at 10 mA cm −2 , a small Tafel slope of 37.6 mV dec −1 , and robust stability at 10 and 100 mA cm −2 . Experimental and theoretical calculations identify the actual active sites as IrNi@NiFeOOH and further reveal that the dynamic structure evolution and self‐optimized dynamic interface electron structure, promoted by heterostructure engineering, boost its OER catalytic performance. Moreover, IrNi@NiFeOOH heterostructure displays strong interface electron interactions and a unique self‐optimized dynamic interface electron structure, resulting in better charge redistribution and adaptive bonding (Ir─O─Ni/Fe bonds). This structure therefore plays a critical role in promoting electron transfer, facilitating the dynamic evolution of reaction intermediates, and reducing the energy barrier of the potential‐determining step, thereby boosting the OER performance. These findings provide new insights into the development of MOF‐based electrocatalysts via heterostructure engineering.