Enhanced visible light photocatalytic degradation of Rhodamine B by Bi/Bi₂MoO₆ hollow microsphere composites

Bi/Bi₂MoO₆ hollow microsphere (BMO-HMS) composites were successfully synthesized via a microwave-assisted reaction of a Bi₂MoO₆ precursor in an ethylene glycol solution using a microwave synthesis system and subsequent annealing in a nitrogen atmosphere. The morphology, structure and photocatalytic performance of the composites in the degradation of Rhodamine B (RhB) were characterized by scanning electron microscopy, X-ray diffraction, electrochemical impedance spectra, UV-vis absorption spectroscopy, Raman spectroscopy and nitrogen adsorption-desorption, respectively. The results show that the BMO-HMS composites exhibit enhanced photocatalytic performance in the degradation of RhB with a maximum degradation rate of 91% under visible light irradiation compared with the pure Bi₂MoO₆. The improved photocatalytic performance is ascribed to the enhanced light absorption and the reduced electron-hole pair recombination with the presence of Bi in the composites.