Electronic, structural, optical, and photocatalytic properties of graphitic carbon nitride

Graphitic carbon nitride (g-C3N4)-based materials exhibit an organized layered porous structure and a band position optimum for the development of various optoelectronic devices and photocatalysts. Hence, a considerable number of experimental and theoretical studies have been carried out to investigate their outstanding chemical and physical properties in both pristine and modified forms. In this study, we investigated the electronic, structural, optical, and photocatalytic properties of g-C3N4 obtained by heating urea in an appropriate self-supporting NH3(g) atmosphere. The X-ray diffraction results revealed that the g-C3N4 nanopowder was crystalline and had a hexagonal structure. The crystallite size varied from 3.61 to 3.49 nm depending on the NH3(g) concentration. The Fourier transform infrared analysis confirmed that g-C3N4 was synthesised successfully. The optical properties of g-C3N4 were investigated on the basis of its photoluminescence spectrum, which showed a broadband with blue region emission (similar to 490 nm). The decay time of g-C3N4 was used to evaluate its photocatalytic performance. An understanding of the structural defects in g-C3N4-based materials can provide an insight into their outstanding chemical and physical properties.