Unlocking the photo-Fenton potential of novel magnetically separable sulfur doped g-C3N4/CoFe2O4 Z-scheme heterojunction systems towards tetracycline removal

The increasing presence of antibiotics in water sources has become a major environmental concern. In this regard, designing of new photocatalysts possessing high visible light response and pertinent redox potentials are prerequisites. Herein, magnetically recoverable sulfur doped g-C₃N₄ (SCN)@CoFe₂O₄ (SCNCoFe) Z-scheme heterostructures were successfully fabricated by employing simple calcination route in which CoFe₂O₄ nanoparticles were allowed to grow over SCN nanosheets. The prepared heterostructures displayed highly efficient photocatalytic removal of tetracyclines i.e., tetracycline (TC) and minocycline (MC), SCNCoFe-20 showed the highest degradation efficiency, with around 94% for both TC and MC within 120 s of visible light irradiation. The mineralization efficacy analysis using total organic carbon removal % validated the practicality of proposed method towards removal of TC and MC from aquatic environment. Photoluminescence and radical quenching studies revealed the enhancement in H₂O₂ assisted photocatalytic degradation of TC and MC via Z-scheme charge transport, which comprehends the substantial synergy effect between photocatalysis and Fenton mechanism. Overall, this work provides a new insight into development of Z-scheme based heterostructures for antibiotics elimination from wastewater.