Constructing Sulfur Vacancy-Rich NiCo₂S₄@MoS₂ Core@shell Heterostructure via Interface Engineering for Enhanced HER...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient non-noble metal electrocatalysts for water splitting is critical.
• Optimizing heterointerfaces and defect engineering are key strategies for enhancing catalyst performance.
• Nickel-cobalt sulfide (NiCo2S4) and molybdenum disulfide (MoS2) are promising materials for electrocatalysis.

Purpose of the Study:

• To comparatively study NiCo2S4-MoS2 heterostructures with different interfacial architectures.
• To elucidate the impact of interfacial design and defect engineering on hydrogen evolution reaction (HER) performance.
• To establish a generalizable strategy for designing high-efficiency non-noble metal electrocatalysts.

Main Methods:

• Synthesis of core@shell NiCo2S4@MoS2 heterostructures via hydrothermal method.
• Preparation of supported NiCo2S4/MoS2 heterostructures using ultrasonic-assisted deposition.
• Comprehensive structural, spectroscopic, theoretical, and electrochemical characterization.

Main Results:

• The core@shell NiCo2S4@MoS2 structure exhibited enhanced charge redistribution and abundant sulfur vacancies.
• The core@shell configuration significantly increased the density of electroactive sites.
• NiCo2S4@MoS2 demonstrated superior HER performance in acidic solution compared to supported heterostructures and single components.

Conclusions:

• A dual-optimization strategy combining interfacial design and vacancy modulation is effective for enhancing electrocatalyst performance.
• The core@shell NiCo2S4@MoS2 heterostructure serves as a highly efficient non-noble metal electrocatalyst for water splitting.
• This approach provides a generalizable paradigm for designing advanced electrocatalysts for energy conversion reactions.