Tuning d ‐Band Center in Tungsten‐Incorporated Ni(OH) 2 Nanosheets with Nickel/Carbon Nanofibers for Promoted Urea Electrooxidation and Its‐Assisted Efficient Hydrogen Production

The urea oxidation reaction (UOR), recognized as an energy-efficient alternative to the oxygen evolution reaction (OER), has garnered considerable scientific interest due to its dual functionality in energy-saving hydrogen (H₂) production and environmental remediation. In this study, tungsten-incorporated nickel hydroxide anchored on nickel-carbon nanofibers (denoted as W-Ni(OH)₂@Ni-CNFs) has been developed through a synergistic electrospinning-carbonization-electrodeposition strategy for high-performance UOR catalysis. Systematic characterizations demonstrate that W incorporation induces favorable surface reconstruction of Ni(OH)₂ and modulates its electronic structure, collectively leading to exceptional electrocatalytic enhancement. The optimized catalyst exhibits remarkable UOR activity with ultralow potentials of 1.351 and 1.547 V versus reversible hydrogen electrode (RHE) at the current densities of 10 and 300 mA cm^-2, respectively, outperforming most benchmark catalysts to date. Density functional theory (DFT) simulations elucidate that W incorporation strategically modulates the d-band center position, strengthening key intermediates adsorption and reducing the reaction energy barrier for the rate-determining step. Furthermore, a urea-assisted water electrolyzer constructed with W-Ni(OH)₂@Ni-CNFs anode and Pt/C cathode achieves a low cell voltage of 1.376 V at 10 mA cm^-2. This configuration exhibits a 6.4-fold enhancement in H₂ evolution rate compared to conventional alkaline water electrolysis, highlighting its substantial energy-saving advantages.