Graphitic carbon nitride (g-C₃N₄) is recognized as one of the most promising metal-free photocatalysts according to its chemical stability, optical activity in the visible region, and structural versatility. Nevertheless, the photocatalytic activity of g-C₃N₄ may usually be restricted by the low efficiency in charge separation and moderate redox potential. In the current study, the photocatalytic material of graphitic carbon nitride has been prepared by the straightforward thermal polycondensation of melamine and has been explored systematically. Through the X-ray diffraction technique, the material has been proved to have ordered layers with an interlayer distance of 0.324 nm, along with an average size of the crystallite of 90.9 nm. Moreover, it has unambiguously been shown that the material possesses considerable absorption in the visible region and has an optical bandgap of 2.61 eV according to the results of the UV-Visible spectra. The thermal properties of the photocatalytic material have been revealed by the thermal analysis, and it is confirmed that the material possesses good stability with few losses in masses at high temperatures along with the characteristic thermal transition at 350 °C. The density functional theory (DFT) calculations were performed with the aim of providing atomic-level validation and mechanistic insight into the electronic structure and reactivity of g-C₃N₄. Calculated frontier molecular orbitals and global quantum chemical descriptors are in good agreement with the experimentally observed semiconducting behavior and point to a favorable balance between electronic stability and charge-transfer capability. Molecular electrostatic potential analysis identifies nitrogen-rich regions as preferential reactive sites, thus supporting the material's photocatalytic and adsorption-driven degradation performance. The combination of experimental characterizations with computational chemistry provides a clear structure-property relationship that ensures g-C₃N₄ is a robust and efficient candidate for solar-driven photocatalysis and environmental remediation.
Abbas et al. (Wed,) studied this question.