Fe, Mo co-doping enhances the OER performance of nickel sulfide nanoflakes for seawater electrolysis

• Published in: Journal of alloys and compounds 2025-01, Vol.1010, p.177480, Article 177480
• Main Authors: Tao, Yunjuan, Xu, Zhikun, Yan, Rui, Sun, Yujing, Lin, Shuangyan
• Format: Article
• Language: English
• Subjects: Electrocatalyst; FeMo-co-doped; Nanoflakes arrays; Oxygen evolution reaction; Seawater electrolysis
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.177480

Development of efficient and corrosion-resistant catalysts for oxygen evolution reaction (OER) offers great promise for seawater electrolysis but remains a challenge. Herein, Fe, Mo-co-doped NiS/Ni3S2 (FeMo-NiSy) rough nanoflakes array on Ni foam has been developed as a high-efficiency OER electrocatalyst for seawater electrolysis. The optimal electrode Fe0.05Mo-NiSy only requires an overpotential of 289 mV to drive 100 mA cm−2 for seawater oxidation, which is 194 mV lower than that of NiSy (483 mV). Based on the experiments and density functional theory (DFT) calculations, the significantly enhanced OER activity can be attributed to the modified electronic structure and the reduced free energy of the potential-limiting step after co-doping of Fe and Mo. Importantly, the Fe0.05Mo-NiSy electrode presents great durability in simulated seawater and natural seawater due to the good corrosion resistance. This study provides new insight into bimetallic co-doping sulfides for seawater oxidation. [Display omitted] •Fe and Mo co-doping tunes the electronic structure and conductivity of NiS/Ni3S2.•The free energy of the potential-limiting step is reduced after co-doping Fe and Mo.•FeMo-NiSy shows remarkable OER activity for seawater electrolysis.•It exhibits a low overpotential 289 mV at 100 mA cm−2 in alkaline seawater.•The overpotential at 100 mA cm−2 decreases 194 mV through co-doping Fe and Mo.