Interfacial Ni–O–Ru Bridges Manipulate d-Band Center of Dual-Metal Site Catalysts for Efficient Water Splitting

Regulating the d-band center (εd) is an effective strategy to enhance the electrocatalytic performance by optimizing the adsorption and desorption of reaction intermediates. However, the targeted control of εd for different reactions remains challenging. Here, we strategically engineer εd to optimize the intermediate adsorption on a dual-metal site catalyst (Ru@NiBDC/NF) via Ni–O–Ru bridges. The synergistic effect of atomically Ru–Ni dual-metal sites in Ru@NiBDC/NF enhances catalytic activity for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), achieving overpotentials of 18 and 230 mV at 10 mA cm–2, respectively. Operando Raman spectra and X-ray absorption spectroscopy reveal that Ru@NiBDC/NF reconstructs into Ru@Ni(OH)2/Ru@NiOOH with abundant Ni–O–Ru bridges during HER/OER. Theoretical calculations indicate that Ni–O–Ru bridge formation facilitates electron redistribution, downshifting εd of Ni sites in Ru@Ni(OH)2 and upshifting it in Ru@NiOOH, respectively. This modulation optimizes the adsorption energies of intermediates, thereby enhancing reaction kinetics and catalytic efficiency.