Surface Engineering for Extremely Enhanced Charge Separation and Photocatalytic Hydrogen Evolution on g-C₃ N₄

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Efficient photocatalytic hydrogen evolution (PHE) is crucial for renewable energy production.
• Graphitic carbon nitride (g-C3N4) shows promise for PHE but is limited by rapid carrier recombination.
• Optimizing carrier separation in g-C3N4 is a key challenge for enhancing PHE efficiency.

Purpose of the Study:

• To enhance the photocatalytic hydrogen evolution (PHE) efficiency of graphitic carbon nitride (g-C3N4).
• To investigate the effect of surface engineering via graphitic carbon ring doping on carrier separation.
• To establish suitable energy band structures and built-in electric fields for improved photocatalysis.

Main Methods:

• Surface engineering of graphitic carbon nitride (g-C3N4) through gradual doping of graphitic carbon rings.
• Characterization of energy band structures and built-in electric fields.
• Evaluation of photocatalytic hydrogen evolution rates.

Main Results:

• Surface engineering successfully introduced graphitic carbon rings into g-C3N4.
• The modified g-C3N4 exhibited optimized energy band structures and built-in electric fields.
• A significant 21-fold improvement in the photocatalytic hydrogen evolution rate was achieved due to enhanced carrier separation.

Conclusions:

• Surface engineering of g-C3N4 with graphitic carbon rings is an effective strategy to enhance carrier separation.
• The established built-in electric fields effectively promote the separation of photoinduced electrons and holes.
• This approach offers a promising pathway for developing highly efficient graphitic carbon nitride-based photocatalysts for hydrogen production.