W doping dominated NiO/NiS₂ interfaced nanosheets for highly efficient overall water splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalytic water splitting is crucial for clean energy, but high-efficiency catalysts are challenging to develop.
• Nickel-based materials show promise but suffer from limited active sites.
• Heteroatom doping and interface engineering are key strategies to enhance catalyst performance.

Purpose of the Study:

• To develop a novel bifunctional electrocatalyst for efficient overall water splitting.
• To investigate the synergistic effects of tungsten (W) doping and NiO/NiS2 nanointerfaces on catalytic activity.
• To improve the electrocatalytic performance of nickel-based materials.

Main Methods:

• Hydrothermal and annealing processes to synthesize W-doped NiO nanosheets on carbon sheets.
• Argon plasma-assisted sulfurization to form W-doped NiO/NiS2 interfaced nanosheets.
• Electrochemical characterization to evaluate overall water splitting performance.

Main Results:

• W doping effectively modifies the electronic structure of nickel, enhancing intrinsic activity.
• The NiO/NiS2 nanointerface provides abundant electroactive sites and improves charge transfer.
• The W-doped NiO/NiS2 bifunctional electrocatalyst achieved a low cell voltage of 1.614 V at 10 mA cm⁻² for overall water splitting.

Conclusions:

• The W-doped NiO/NiS2 interfaced nanosheets represent a highly efficient and bifunctional electrocatalyst for overall water splitting.
• The combined strategy of W doping and interface engineering significantly boosts electrocatalytic performance.
• This work offers a promising pathway for designing advanced electrocatalysts for clean energy applications.