Preparation of Mn0.8Cd0.2S Nanoparticles and their Photocatalytic Behavior for Degradation of Tetracycline in Water

Antibiotics in water pose a significant threat to human health and the environment. A promising solution to this issue is the utilization of photocatalysis, which can efficiently and environmentally make antibiotics convert into harmless substances. Hence, the development of an effective photocatalyst is crucial. In this study, Mn_0.8Cd_0.2S nanoparticles were prepared via a solvothermal process and subsequently evaluated for their photocatalytic performance in the degradation of tetracycline in water. The results demonstrated that Mn_0.8Cd_0.2S nanoparticles exhibit exceptional photocatalytic activity. Under irradiation for 120 min, tetracycline (5 × 10⁻⁵ mol L⁻¹) can be completely degraded, ultimately converting into CO₂ and H₂O. Mechanistic investigations revealed that the primary reactive species involved in the degradation process are holes and superoxide radicals, with the latter playing a dominant role. Furthermore, the Mn_0.8Cd_0.2S nanoparticles demonstrated excellent salt tolerance and maintained considerable photocatalytic efficiency even at extremely low concentrations of tetracycline. Remarkably, when the tetracycline concentration was as low as 1 × 10⁻⁷ mol L⁻¹, a complete degradation (100%) was still achieved after 240 min of irradiation. These findings highlight the potential of Mn_0.8Cd_0.2S nanoparticles as a highly efficient photocatalyst for the removal of antibiotic contaminants from drinking water.

Graphical Abstract