Self-Supported Ru/P Dual-Doped CoMoO₄ Nanorod Arrays as a Bifunctional Electrocatalyst for Overall Water Splitting

Developed an efficient bifunctional electrocatalyst for alkaline and seawater environments, crucial for sustainable hydrogen production. In this study, Ru/P dual-doped self-supported cobalt molybdate (Ru/P-CoMoO₄) nanorod array catalysts with large surface areas and abundant catalytic sites are synthesized. Additionally, Ru/P co-doping optimizes the electronic structure to facilitate electron transfer and enhance reaction kinetics. Density-functional theory calculations reveal this modulation also optimizes H* adsorption and confers Cl⁻ poisoning resistance, resulting in superior hydrogen evolution reaction (HER)/oxygen evolution reaction (OER) performance in alkaline freshwater and seawater. Consequently, the self-supported Ru/P-CoMoO₄ electrode delivers exceptional HER performance (η₁₀ = 29 mV, η₁₀₀₀ = 231 mV), OER performance (η₁₀₀ = 308 mV, η₅₀₀ = 399 mV). The catalyst also shows outstanding overall water splitting (OWS) performance, requiring only 1.535 V in alkaline media and 1.581 V in alkaline seawater to achieve a current density of 10 mA cm⁻², with excellent long-term durability of 200 h at 100 mA cm⁻². This work effectively deploys sustainable green-hydrogen systems powered by wind and solar energy, offering a viable strategy for future large-scale sustainable hydrogen production. © 2025 Wiley-VCH GmbH.