3D V–Ni3S2@CoFe-LDH core-shell electrocatalysts for efficient water oxidation. (18th November 2021)

• Record Type: Journal Article
• Authors: Tong, Rui; Xu, Miao; Huang, Haiming; Wu, Chengrui; Luo, Xiao; Cao, Minglei; Li, Xingxing; Hu, Xiaosai; Wang, Shuangpeng; Pan, Hui
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 80(2021)
• Page Start: 39636
• Page End: 39644
• Publication Date: 2021-11-18
• Subjects: OER -- V–Ni3S2@CoFe-LDH -- Core-shell -- Overpotential -- Tafel slope; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2021.09.190
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Studying cheap and efficient electrocatalysts is of great significance to promote the sluggish kinetics of oxygen evolution reaction (OER). Here, we adopted a simple two-step method to successfully prepare the 3D V–Ni3 S2 @CoFe-LDH core-shell electrocatalyst. The V–Ni3 S2 @CoFe-LDH/NF shows excellent OER performance with low overpotential (190 mV at 10 mA/cm 2 and 240 mV at 50 mA/cm 2 ), small Tafel slope (26.8 mV/dec) and good long-term durability. Excitingly, to reach the same current density, V–Ni3 S2 @CoFe-LDH/NF electrode even needs much smaller overpotential than RuO2 . Furthermore, the outstanding OER activity of V–Ni3 S2 @CoFe-LDH/NF is ascribed to the following reasons: (1) V–Ni3 S2 nanorod cores improve the conductivity and ensure the fast charge transfer; (2) CoFe-LDH nanosheets interconnected with each other provide more exposed active sites; (3) the unique 3D core-shell structures are favorable for electrolyte diffusion and gas releasing. Our work indicates that building 3D core-shell heterostructure will be a useful way to design good electrocatalysts. Graphical abstract: Image 1 Highlights: V–Ni3 S2 @CoFe-LDH/NF showed OER overpotential of 190 mV at 10 mA/cm 2 . V–Ni3 S2 nanorod cores improve the conductivity and accelerate charge transfer. CoFe-LDH nanosheets supply easily accessible catalytic sites. The core-shell nanostructure benefits electrolyte diffusion and gas releasing.