Modulating the Structure of Graphitic Carbon Nitride for Accelerated Charge Separation and Enhanced Hydrogen...

Area of Science:

• Materials Science
• Photocatalysis
• Green Chemistry

Background:

• Graphitic carbon nitride (CN) is a metal-free photocatalyst with tunable properties.
• Pristine CN suffers from rapid carrier recombination and low electrical conductivity, limiting its practical applications.
• Developing efficient and stable photocatalysts is crucial for sustainable energy solutions.

Purpose of the Study:

• To enhance the molecular structure and photocatalytic performance of graphitic carbon nitride (CN).
• To overcome the limitations of rapid carrier recombination and low electrical conductivity in pristine CN.
• To synthesize and characterize a novel CN-based composite material for improved hydrogen evolution.

Main Methods:

• Copolymerization of graphitic carbon nitride (CN) with organic molecules, specifically barbituric acid.
• Structural and morphological characterization of the synthesized materials.
• Evaluation of photocatalytic activity through hydrogen evolution rate measurements and apparent quantum efficiency determination.

Main Results:

• The optimized photocatalyst, termed CNBM, exhibited a hydrogen evolution rate of 23.13 mmol·h^-1·g^-1, a 118-fold improvement over pristine CN.
• An apparent quantum efficiency of 87.9% at 420 nm was achieved for CNBM.
• Enhanced surface area, improved crystallinity, and facilitated electron delocalization were observed in CNBM, attributed to the incorporation of barbituric acid.

Conclusions:

• Copolymerization is an effective strategy to enhance the photocatalytic performance of graphitic carbon nitride (CN).
• The developed CNBM material demonstrates superior hydrogen evolution activity and efficiency compared to pristine CN.
• The enhanced properties of CNBM, including increased surface area and improved charge carrier separation, make it a promising candidate for photocatalytic applications.