Graphitic Carbon Nitride-based Photocatalysts for Environmental Remediation of Organic Pollutants

Graphitic carbon nitride (g-C3N4) is an extraordinary semiconductor photocatalyst (PC), which transforms solar energy into chemical energy for the photodisintegration of several noxious organic contaminants into non-toxic derivatives. Polymeric g-C3N4 is a metal-free PC with high chemical stability, eco-friendly composition, and suitable energy band potential that absorb a significant portion of the solar spectrum. Despite its outstanding characteristics, g-C3N4 has some limitations, including low visible light absorption, low surface area, and rapid recoupling of charge carriers. These limitations over-shaded its proficient efficiency as a PC. The current g-C3N4 related research focuses on developing g-C3N4 nanocomposites (NCs) with high-surface-area, broad light-absorbing, and reduced recombination via physicochemical modifications. This review highlights the latest developments in the synthesis and application of pristine g-C3N4 and its NCs with inorganic constituent and nanomaterials. A critical analysis of the strategies to enhance g-C3N4's photocatalytic efficiency via excited charge separation and visible light absorption is also presented. Furthermore, the photocatalytic degradation of organic pollutants (OPs), including dyes, phenol, antibiotics, and pharmaceutical drugs, is summarized herewith.