Structural and compositional tuning in g-C₃N₄ based systems for photocatalytic antibiotic degradation

The uncontrolled and unethical release of pharmaceutical contaminants into aquatic sources have severe adversities, including the possible emergence of antimicrobial-resistant bacteria. Photocatalysis utilizing semiconductor heterostructures is a greener and sustainable option for the effective degradation of organic contaminants into relatively harmless by-products. Visible/sunlight active graphitic carbon nitride based photocatalysts have been explored for antibiotic degradation (Tetracycline, Doxycycline, Oxytetracycline, Sulfamethoxazole, Amoxicillin) owing to their excellent chemical/thermal stability, tunable photophysical properties and facile methods of synthesis. The properties were further enhanced by heterostructure formation with other compatible semiconductors, elemental/molecular doping and through the creation of hierarchically porous structures. Moreover, nanocomposite formation with high surface area porous frameworks induces adsorptive photocatalysis imparting bifunctionality and alleviating secondary remediation measures for regeneration of the catalysts. The review summarizes the efforts in developing C₃N₄ based systems for the effective degradation of various antibiotics. Finally, an outlook on essential improvements is forecasted.