Single-atom Ru anchored on Co3S4 nanowires enabling ampere-level water splitting for multi-scenarios green energy-to-hydrogen systems

Abstract

Versatile systems capable of high current densities (exceeding 1 A cm⁻²) are essential for advancing hydrogen energy from theoretical to practical applications. Herein, single-atom Ru anchored on cobalt tetrasulfide (Ru-Co₃S₄) nanowires were proposed as an exceptional performance electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Microstructural analyses, X-ray absorption spectroscopy, and theoretical calculations demonstrate that the Ru atoms doped in Co₃S₄ nanowire with the formation of three-coordinated Ru-S species, which can effectively prevent excessive oxidation of Ru and improve stability. Benefiting from high intrinsic activity, fast charge transfer rate and large amounts of active sites, the Ru-Co₃S₄ catalyst demonstrates a low overpotential of 306 mV for HER and 460 mV for OER at 1 A cm⁻² in 1 M KOH aqueous medium. Additionally, Ru-Co₃S₄ catalysts represent 9.5 times in mass activity (4.27 A mg⁻¹_Ru) compared to Pt/C (0.45 A mg⁻¹_Pt). Ru-Co₃S₄ has proven effective for hydrogen generation through electrolysis in both alkaline freshwater and seawater settings. Moreover, the integrated utilization of wind and solar energy in water splitting for hydrogen production systems offers the potential of single atoms Ru doped catalyst for large-scale hydrogen production in the future.