F-doping induced low-barrier interface in RuNi-F-NiMoO4 heterostructure for efficient urea-assisted hydrogen evolution via seawater splitting

Amidst the escalating global energy crisis, the quest for efficient electrocatalysts for water splitting has become increasingly imperative. Herein, we develop a bifunctional electrocatalyst comprising RuNi alloy nanoparticles anchored on fluorine-doped NiMoO 4 nanorods (RuNi-F-NiMoO 4 ), engineered for efficient hydrogen production from seawater and urea oxidation reactions. The strategic F doping effectively reduces the difference in work functions and modulates the electronic interactions between the RuNi alloy and the NiMoO 4 substrate, enhancing electron transfer kinetics and significantly improving electrocatalytic activity and stability. Notably, the RuNi-F-NiMoO 4 exhibits outstanding hydrogen evolution reaction performance in both alkaline freshwater (248 mV at 1 A cm −2 ) and alkaline seawater (277 mV at 1 A cm −2 ), enabling industrial-scale high-current–density hydrogen production and maintaining durability over 1,000 h at 100 mA cm −2 in alkaline seawater. Furthermore, RuNi-F-NiMoO 4 achieves a current density of 1 A cm −2 at a low potential of 1.59 V during the urea oxidation reaction, and facilitates a complete urea total cracking system operating at 1.88 V at 1 A cm −2 in alkaline seawater, thereby reducing energy consumption for hydrogen production. This work offers a promising avenue for the development of efficient electrocatalysts in seawater electrolysis and urea oxidation, potentially advancing sustainable energy technologies.