Application of graphitic carbon nitrides in developing polymeric membranes: A review

Membrane separation processes have been considered as general techniques for separation and purification of water, for they guarantee a number of worldwide advantages in terms of their economics and outstanding practical selectivity. However, fouling restricts the efficiency of membranes, necessitating modification of their bulk and surface characteristics. Incorporation of nanomaterials into the membrane matrix has been intended as a prominent strategy, where carbon-based nanostructures played a key role in diminishing fouling. Graphitic carbon nitride (g-C₃N₄) composed of carbon and nitrogen has attracted significant attentions in membrane fabrication owing to its hydrophilic nature, acceptable thermal stability and photocatalytic property. In this review, a brief explanation of the history of g-C₃N₄ was provided, followed by classification and explanation of different ways attempted in fabrication of g-C₃N₄ membranes. In addition, the influence of g-C₃N₄ on the efficiency of membrane processes was comprehensively discussed. Finally, the challenging aspects of the future usage of g-C₃N₄ in industrial scale processes were discussed.