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The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dom-inated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/NiSe@Fe203)is fabricated via two-step hydrothermal method,which exhibits a low over-potential of 220 mV(or 282 mV)at 10 mA/cm2(or 200 mA/cm2),a small Tafel slope of 36.9 mV/dec,and long-term stability(～230 h)in 1 mol/L KOH for OER.X-ray photoelectron spectroscopy and X-ray absorption spectroscopy reveal the(oxy)hydroxide-rich surface and strong coupling interface between NiSe and Fe2O3 via the Fe-Se bond.Density functional theory calculation suggests that the d-band center and electronic state of NiSe@Fe2O3 heterojunction are well optimized due to the formation of Fe-Se bond,which is favorable for the enhanced OER activity because of the easy adsorption of oxygen-containing intermediates and desorption of O2 in the OER process.In addition,the unique core-shell structure and robust bonding interface are responsible for the good stability for OER.This work provides fundamental insights on the bonding effect that determine the performance of OER electrocatalyst.