Thermal and hydrothermal synthesis of WO₃ nanostructure and its optical and photocatalytic properties for the degradation of Cephalexin and Nizatidine in aqueous solution

Pharmaceuticals have recently become a serious environmental concern due to the increase in the human population, industrial development and modern lifestyles. The optical property and photocatalytic degradation of Cephalexin and Nizatidine were investigated using nanostructured WO₃ under visible photon irradiation. The WO₃ nanostructures were synthesised through direct heating and hydrothermal method using WCl₆ as a precursor for tungsten. The prepared WO₃ was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS) analysis and Photoluminescence analysis (PL). The optical properties were investigated by UV–vis DRS and PL were WO₃ nanostructures exhibited band gaps from 2.60 to 2.70 eV and an emission covering the blue-violet region. The photocatalytic activity studies revealed that the prepared WO₃ exhibit good photocatalytic performance, degrading the aqueous pharmaceutical solutions of Cephalexin and Nizatidine under visible light illumination.