Graphitic carbon nitride: Synthesis and characterization

Abstract The graphitic carbon nitride (g-C3N4) is a two-dimensional, nonmetallic, ᴫ-conjugated polymeric material. g-C3N4 can be produced by polymerizing the carbon- and nitrogen-containing compounds such as cyanamide, dicyandiamide, or melamine. The extent of polymerization and condensation reaction controls the property and reactivity of the final product. g-C3N4 with a band gap of about 2.4–2.7 eV accounts for semiconductors applicable in nanoelectronic and spintronic devices. Its electronic structure can be modulated in a controlled manner by doping other materials or by chemical functionalization. It has been known as a metal-free, cheap, and visible-light-responsive photocatalytic compound. Its high chemical and thermal stability, and large specific surface area have been attracting researchers of various fields. The nanostructured properties of g-C3N4 can be modified and tuned by surface functionalizing, intercalating, or compositing with suitable compounds. Regarding their large specific surface area and high chemical stability, the g-C3N4 based compounds have found promising applications in diverse interdisciplinary areas such as photocatalysis, photoelectronics, and photodegradation. This chapter is intended to describe the history of g-C3N4, its different structures, properties, synthesis methods, and characterization.