NiPS₃ Nanosheet-Graphene Composites as Highly Efficient Electrocatalysts for Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Efficient water splitting is crucial for sustainable hydrogen production.
• Two-dimensional (2D) materials offer unique properties for high-performance electrocatalysis.
• Developing novel electrocatalysts is key to advancing water splitting technologies.

Purpose of the Study:

• To develop and evaluate few-layer NiPS3 nanosheet-graphene composites as electrocatalysts for the oxygen evolution reaction (OER).
• To investigate the synergistic effects between NiPS3 nanosheets and graphene for improved OER activity.
• To compare the performance of these novel composites with existing OER catalysts.

Main Methods:

• Synthesis of few-layer NiPS3 nanosheets and their integration with graphene.
• Electrochemical characterization of pure NiPS3 nanosheets and NiPS3-graphene composites for OER.
• Performance evaluation including overpotential, current density, Tafel slope, and stability tests.

Main Results:

• Pure NiPS3 nanosheets exhibited an OER overpotential of 343 mV at 10 mA cm⁻², comparable to IrO2 and RuO2.
• NiPS3-graphene composites showed significantly enhanced OER activity due to synergistic effects.
• The optimized composite achieved a low overpotential of 294 mV at 10 mA cm⁻², a small Tafel slope of 42.6 mV dec⁻¹, and excellent stability.

Conclusions:

• Few-layer NiPS3 nanosheet-graphene composites represent a highly promising class of electrocatalysts for OER.
• The synergistic interaction between NiPS3 and graphene leads to superior catalytic performance.
• These materials offer a cost-effective and efficient alternative to traditional OER catalysts for hydrogen production.