Low-Coordinate Iridium Oxide Confined on Graphitic Carbon Nitride for Highly Efficient Oxygen Evolution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing highly active and durable electrocatalysts for the oxygen evolution reaction (OER) is crucial for energy conversion technologies.
• Iridium oxide (IrO2)-based materials are promising OER catalysts but often suffer from limited stability and activity.

Purpose of the Study:

• To design and synthesize novel Iridium oxide/graphitic carbon nitride (IrO2/GCN) heterostructures for efficient acidic OER.
• To investigate the role of GCN nanosheets in enhancing the dispersion, stability, and catalytic activity of IrO2 nanoparticles.

Main Methods:

• Synthesis of IrO2 nanoparticles confined on superhydrophilic GCN nanosheets.
• Characterization of the heterostructure's physical and chemical properties.
• Electrochemical evaluation of the catalyst's performance in acidic media for OER.

Main Results:

• The IrO2/GCN heterostructure exhibited a superhydrophilic surface, promoting active site exposure and mass diffusion.
• Strong interaction between IrO2 and GCN reduced the coordination number of Ir atoms, inducing lattice strain and enhancing electron density.
• The optimized IrO2/GCN catalyst demonstrated superior mass activity compared to other IrO2-based catalysts and showed good durability.

Conclusions:

• IrO2/GCN heterostructures are effective for enhancing acidic OER performance.
• The GCN support plays a key role in stabilizing IrO2 NPs and improving catalytic efficiency.
• These findings offer a promising pathway for developing advanced electrocatalysts for energy applications.