Constructing three-dimensional porous Ni/Ni₃S₂ nano-interfaces for hydrogen evolution electrocatalysis under alkaline...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Designing cost-effective, highly active, and stable electrocatalysts for the hydrogen evolution reaction (HER) in alkaline media remains a significant challenge.
• Current industrial standards, like nickel metal, face limitations in performance and efficiency for water splitting applications.

Purpose of the Study:

• To develop a novel three-dimensional (3D) porous nano-network structure for efficient HER catalysis.
• To investigate the synergistic effects at Ni/Ni3S2 hetero-interfaces for enhanced water splitting.
• To provide a low-cost, earth-abundant alternative to existing electrocatalysts.

Main Methods:

• Facile synthesis of a 3D porous Ni/Ni3S2 nano-network on carbon cloth.
• Electrochemical characterization of the material for HER activity in alkaline solutions.
• Density Functional Theory (DFT) calculations to elucidate the interfacial synergistic mechanism.

Main Results:

• The synthesized Ni/Ni3S2 nano-network exhibits excellent HER activity, achieving 10 mA cm-2 at 95 mV.
• A low Tafel slope of 66 mV dec-1 was recorded, indicating efficient catalytic kinetics.
• DFT calculations confirmed a synergetic effect at the Ni/Ni3S2 interface, facilitating water splitting through heterolytic H2O splitting and weakened Ni-H binding.

Conclusions:

• The 3D porous Ni/Ni3S2 nano-network demonstrates superior HER performance compared to nickel metal.
• The interfacial synergy between Ni and Ni3S2 is key to the enhanced catalytic activity.
• This material offers a promising, earth-abundant electrocatalyst for efficient hydrogen production via water splitting.