Visible-light-driven photo-Fenton degradation of ceftriaxone sodium using SnS2/LaFeO3 composite photocatalysts

Abstract

A series of x-SnS₂/LaFeO₃ (x = 5–50 wt%, x-SN/LFO) composite photocatalysts have been successfully synthesized for ceftriaxone sodium (CRS) degradation via a visible-light-driven photo-Fenton process. These as-obtained materials were characterized through XPS, DRS, photocurrent response and so on, to explore the reasons for the enhanced photocatalytic performance. These composites have a heterostructure with SnS₂ sheets tightly and randomly attached to the surface of LaFeO₃, effectively boosting the separation and transfer of photogenerated-charge. Meanwhile, the photo-Fenton process was initiated by the additional H₂O₂, which utilized some photogenerated-electrons and then to some extent facilitated the separation of photogenerated electron–hole pairs. According to corrected photocatalytic degradation experimental data, the efficient photo-Fenton system with 20-SN/LFO as the catalyst realized a CRS removal efficiency of 87.54% and displayed a reaction rate constant (0.01175 min⁻¹) about 1.80 and 2.39 times higher than those of single LFO (0.00652 min⁻¹) and SN (0.00492 min⁻¹), respectively. Therefore, a well-designed 20-SN/LFO composite photocatalyst reveals good potential application in the effective treatment of pharmaceutical sewage.