Graphitic carbon nitride based nanocomposites: a review

Area of Science:

• Materials Science
• Nanotechnology
• Photocatalysis

Background:

• Graphitic carbon nitride (g-C(3)N(4)) is a promising, earth-abundant visible light photocatalyst with a 2D structure and tunable electronic properties.
• Pure g-C(3)N(4) exhibits limited photocatalytic activity due to rapid recombination of photo-generated electron-hole pairs.
• g-C(3)N(4)'s unique electronic structure makes it an excellent candidate for integration into nanocomposites to improve performance.

Purpose of the Study:

• To classify and summarize g-C(3)N(4)-based nanocomposite systems for enhanced photocatalysis.
• To elaborate on the underlying mechanisms responsible for photocatalytic activity enhancement in these nanocomposites.
• To review the fabrication methods, structures, and applications of g-C(3)N(4)-based nanocomposites.

Main Methods:

• Classification of g-C(3)N(4)-based nanocomposites into six primary systems based on their photocatalytic mechanisms.
• Detailed description of fabrication methods and heterojunction structures.
• Analysis of mechanisms like p-n junctions, Schottky junctions, and surface plasmon resonance (SPR) for performance enhancement.

Main Results:

• Six main categories of g-C(3)N(4)-based nanocomposites were identified: metal-free heterojunctions, metal/metal oxide/sulfide heterojunctions, composite oxides, halide heterojunctions, noble metal heterostructures, and complex systems.
• Mechanisms including p-n junctions, Schottky junctions, SPR, photosensitization, and superconductivity contribute to enhanced photocatalytic activity.
• g-C(3)N(4) nanocomposites demonstrate broad applicability in environmental remediation and energy conversion.

Conclusions:

• g-C(3)N(4)-based nanocomposites offer significantly improved photocatalytic performance compared to pure g-C(3)N(4).
• The strategic coupling of g-C(3)N(4) with various materials and the utilization of specific junction mechanisms are key to boosting efficiency.
• These advanced nanomaterials hold substantial potential for addressing environmental pollution and energy challenges, with ongoing research focusing on future directions.