Defects enriched carbon nitride sponge with high surface area for enhanced photocatalytic hydrogen evolution

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Traditional photocatalysts have limited efficiency for sustainable hydrogen production.
• Innovative materials are needed to overcome these limitations.

Purpose of the Study:

• To synthesize a novel 3D sponge-like porous carbon nitride (SCN-x) material.
• To enhance photocatalytic hydrogen production efficiency and stability.

Main Methods:

• Synthesized SCN-x via removal of unstable organic frameworks.
• Characterized SCN-x for surface area, structure, and defects.
• Evaluated photocatalytic hydrogen production under visible light and natural sunlight.

Main Results:

• SCN-x exhibited a highly interconnected network and high surface area (116.5 m²/g).
• Defects introduced, including oxygen atoms, modulated band structure and increased active sites.
• Optimal SCN-0.5 showed an 86.6-fold increase in hydrogen production rate compared to pure carbon nitride (PCN).
• A record-high hydrogen evolution rate of 1663.5 μmol·h⁻¹·g⁻¹ was achieved with 2SCN-0.5 under natural sunlight.

Conclusions:

• The novel SCN-x material offers a promising metal-free photocatalyst for efficient hydrogen production.
• The defect engineering and high surface area strategy is effective for enhancing photocatalytic performance.
• This method enables efficient large-scale hydrogen production using natural sunlight.