Photocatalytic performance of g-C3N4 based nanocomposites for effective degradation/removal of dyes from water and wastewater

The world is concerned about the hazardous effect of dyes that pose a threat to the ecosystem. It is therefore essential to remove these dyes from the aquatic system by using suitable methods. Among all the methods available, photodegradation using graphitic carbon nitride (g-C₃N₄) is suitable and efficient for the removal of dyes from water and wastewater. The pure g-C₃N₄ has low photocatalytic activity because it has a low surface area, which results in insufficient sunlight adsorption. Doping of graphitic carbon nitride was carried out to increase the photodegradation efficiency by enhancing light absorption, providing charge separation and transportation, and increasing the charge carrier lifetime. Various metals and non-metal doped g-C₃N₄ were found to be the most effective and privileged photocatalysts for the degradation of industrial effluents in recent times. This review highlights the heterojunction-based g-C₃N₄ and its enhanced photodegradation of the dyes. It also puts light on making the doped CNS (Carbon Nitride Sheets) nanocomposites through various techniques and on the dyes that are photodegraded using various catalysts. The photodegradation of dyes is mainly carried out under visible light radiation, as it is highly cost-effective. This heterojunction-based g-C₃N₄ shows promising results for the photocatalytic elimination of pollutants from the aqueous phase. In this review, the working principle and mechanism of the g-C₃N₄ photocatalysts are also discussed. Prospects and challenges faced are also discussed in this article.