Chapter 2 - Synthesis, structure, and properties of graphitic carbon nitride

Abstract

Graphitic carbon nitride (g-C3N4) having an organized layered nature displays a unique band structure. The optimal band structure, followed by thermal and chemical robustness, makes them a promising candidate for various applications. Graphitic-C3N4 was appraised for its structure, stability, texture control, range of modification strategies, and its widespread applications. Several experimental and theoretical studies were reported on g-C3N4 regarding their exceptional electronic structure, and physical and chemical properties. Graphitic carbon nitrides polymerize in high N:C ratios, and each layer is composed of carbon and nitrogen heterocycles with either triazine (C3N3) or heptazine (C6N7) rings connected via sp2-bonded nitrogen atoms (N(C)3 units) or NH groups. A variety of compositions are reported following CxNyHz structural formula, from amorphous to polycrystalline nature. The structure and properties of graphitic carbon nitride mainly depend on the synthesis strategies; hence, several challenges persist in the assessment as well as calibrating the basic functionalities of g-C3N4. It is very important to describe the structural and chemical characteristics of g-C3N4 for their functional performance. Here, we describe the lattice and electronic structure as well as the chemical environments of graphitic carbon nitride. Also, we elaborate on various synthesis strategies as well as the standard procedures for tuning the characteristics of the graphitic carbon nitride compound.