Self‐Supported Ru/P Dual‐Doped CoMoO 4 Nanorod Arrays as a Bifunctional Electrocatalyst for Overall Water Splitting

Abstract 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‐CoMoO 4 ) 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‐CoMoO 4 electrode delivers exceptional HER performance ( η 10 = 29 mV, η 1000 = 231 mV), OER performance ( η 100 = 308 mV, η 500 = 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.