Enhanced photocatalytic performance of transition metal doped Bi ₂O₃ nanoparticles under visible light irradiation

Transition metal (M=Ni and Zn) doped Bi₂O₃ nanoparticles were prepared by the precipitation method to enhance the photocatalytic activity of Bi₂O₃. The as-prepared nanoparticles were characterized by different techniques such as powder-X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis-DRS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and photoluminescence (PL) techniques. The photocatalytic activity was evaluated by the degradation of malachite green (MG) dye under visible light irradiation. The results revealed that Ni doped Bi₂O₃ (Ni-Bi ₂O₃) exhibited higher photocatalytic activity when compared to that of other photocatalysts. A set of optimized conditions such as pH, catalyst concentration and initial dye concentration on the photodegradation of MG were investigated in detail.