Graphitic carbon nitrides (g-C3N4) with comparative discussion to carbon materials

Graphitic carbon nitride g-C3N4 was reviewed on its structure, synthesis, texture control, modification and applications, associating with the comparative discussion to carbon materials. Its basic structural unit is a layer of either triazine or heptazine cores consisting of C and N atoms, similar with a layer of hexagonal carbon rings of most of carbon materials. Fundamental synthesis process of g-C3N4 is pyrolysis of its precursors associated with different techniques, such as chemical vapor deposition, pressurizing, templating, doping, etc., as those applied for the synthesis of carbon materials. However, the properties of g-C3N4 are quite different from those of carbon materials; the former is hydrophilic but the latter is hydrophobic, and the former is photoactive for visible light but the latter is non-active. Here, g-C3N4 is reviewed on its structure, synthesis, texture control and modification, and application with comparative discussion to carbon materials.