Enhancing the d/p‐Band Center Proximity with Amorphous‐Crystalline Interface Coupling for Boosted pH‐Robust Water Electrolysis

Abstract Rationalizing non‐precious pH‐robust electrocatalysts is a crucial priority and required for multi‐scenario hydrogen production customization. Herein, an amorphous–crystalline CoBOx/NiSe heterostructure is theoretically profiled and constructed for efficient and pH‐robust water electrolysis. The crystalline lattice confinement induces a CoCo bond shortening and a B‐site delocalization on amorphous CoBOx, resulting in a decreased d‐p band center difference (Δεd‐p) toward the balanced intermediates adsorption/desorption. Accordingly, the CoBOx/NiSe heterostructure exhibits efficient and robust hydrogen/oxygen evolution reaction (HER/OER) catalytic activity in different electrolytes. Of particular note, it achieves ultralow overpotentials in both the beyond‐Pt HER (14.5 mV) and OER (229.1 mV) at 10 mA cm−2 under an alkaline electrolyte, and reaches an industrial‐level OER current density of 2 A cm−2. Water electrolysis is stably delivered with a low η10 voltage of 1.48 V. The incorporation of such d‐p orbitals at the amorphous–crystalline interface puts forward new opportunities in rationally designing advanced non‐precious electrocatalysts for water electrolysis.