Multifunctional Ni₃S₂@NF-based electrocatalysts for efficient and durable electrocatalytic water splitting

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Transition-metal sulfides (TMSs) are promising electrocatalysts but suffer from poor stability and activity.
• Electrocatalytic water splitting is crucial for clean energy production.

Purpose of the Study:

• To design and synthesize a hierarchical nanostructured electrocatalyst for improved water splitting.
• To investigate the synergistic effects of CeO2 decoration on NiCo-layered double hydroxide (LDH) coupled with Ni3S2 for enhanced electrocatalytic performance.

Main Methods:

• Fabrication of a hierarchical nanostructure: Ni2Co1 LDH-CeO2/Ni3S2@NF on Ni foam.
• Electrochemical characterization including overpotential and Tafel slope measurements in alkaline electrolyte.
• Systematic experimental analysis and theoretical calculations to elucidate the catalytic mechanism.

Main Results:

• The Ni2Co1 LDH-CeO2/Ni3S2@NF electrocatalyst exhibited low overpotentials (250 mV for HER, 300 mV for OER at 100 mA cm-2) and favorable Tafel slopes (92 mV dec-1 for HER, 52 mV dec-1 for OER).
• The catalyst demonstrated remarkable long-term stability for water splitting.
• Analysis revealed that the porous Ni3S2@NF framework, NiCo LDH nanosheets, and oxygen-vacancy-rich CeO2 synergistically enhance catalytic kinetics.

Conclusions:

• The rational design of the Ni2Co1 LDH-CeO2/Ni3S2@NF electrocatalyst significantly improves water splitting efficiency and stability.
• The synergistic interplay between different components at the interface is key to optimizing electrocatalytic performance.
• This work offers a promising strategy for developing efficient and durable electrocatalysts for future energy applications.