Structural Distortion of g-C₃N₄ Induced by a Schiff Base Reaction for Efficient Photocatalytic H₂ Evolution

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Photocatalytic hydrogen (H₂) evolution via water splitting offers a sustainable energy solution.
• Graphitic carbon nitride (g-C₃N₄) is a promising photocatalyst but suffers from limited visible light absorption and charge carrier recombination.
• Addressing these limitations is crucial for efficient solar fuel production.

Purpose of the Study:

• To synthesize a novel -C=N- doped g-C₃N₄ material.
• To enhance the visible light response and photocatalytic activity of g-C₃N₄ for H₂ evolution.
• To investigate the structural and electronic modifications induced by -C=N- doping.

Main Methods:

• Synthesis of -C=N- doped g-C₃N₄ using a Schiff base reaction.
• Characterization of the material's structure, optical, and electronic properties.
• Evaluation of photocatalytic H₂ evolution performance under visible light irradiation.

Main Results:

• The -C=N- doping induced structural distortions and facilitated n-π* electronic transitions.
• Light absorption was extended to 600 nm, and heterogeneous π-conjugated electron distribution improved charge carrier separation.
• The doped g-C₃N₄ achieved a H₂ evolution rate of 1050.13 μmol/g/h, 5.9 times higher than pristine g-C₃N₄.

Conclusions:

• Schiff base reaction is an effective method to introduce -C=N- groups into g-C₃N₄.
• The doped g-C₃N₄ exhibits superior photocatalytic activity due to enhanced light absorption and charge separation.
• This work provides a new strategy for designing advanced graphitic carbon nitride photocatalysts for sustainable hydrogen production.