Hydrothermal synthesis of CdS sub-microspheres for photocatalytic degradation of pharmaceuticals

Visible light active CdS were synthesised through a hydrothermal method followed by evaluation of their efficiency in the photodegradation of acetaminophen and levofloxacin. The microspheres were characterised by various physico-chemical techniques such as SEM, UV-Vis, XRD and XPS. The microspheres of about 0.5 mu m size were observed to have lower band gap energy of about 2.26 eV. XPS analysis confirmed the formation of impurity-free CdS microspheres. Photocatalytic degradation studies using visible light from LEDs (455 nm) showed high degradation of the two drugs. Up to 85% of the acetaminophen and 70% of the levofloxacin were degraded in 240 min. CdS microspheres are promising visible light active photocatalyts for the degradation of pharmaceuticals such as acetaminophen and levofloxacin in water.