Visible Light Driven Photo-Catalytic Degradation of Fluoroquinolone Antibiotic Drug Using Bi₂WO₆ Spheres Composed of Fluffy Nanosheets

Herein, we report the synthesis and characterization of Bi₂WO₆ spheres composed of fluffy thin nanosheets prepared by simple and facile hydrothermal process. The synthesized Bi₂WO₆ spheres were characterized in detail to examine the morphological, structural, optical and photocatalytic properties. The detailed morphological characterizations, done by scanning electron microscopy, revealed that the synthesized Bi₂WO₆ spheres are made by the accumulation of several Bi₂WO₆ thin nanosheets. The nanosheets are arranged in such a special manner that they made specific sphere-shaped morphologies. The detailed structural properties confirmed that the prepared Bi₂WO₆ spheres possess well-crystallinity and orthorhombic crystal structure. The detailed UV-DRS and room-temperature photoluminescence (PL) studies confirmed good optical properties for the synthesized Bi₂WO₆ spheres. Finally, the photocatalytic degradation of a fluoroquinolone antibiotic, ofloxacin, was studied under visible light irradiation in aqueous phase using Bi₂WO₆ spheres as catalyst. By detailed photocatalytic experiments, it was found that ∼73% ofloxacin was degraded in 120 minutes in presence of Bi₂WO₆ spheres under visible light irradiation. Interestingly, the photocatalytic kinetic studies confirmed that the photocatalytic process followed the pseudo first order reaction kinetics with rate constant (k) of 0.00926 min^–1. The observed results demonstrate that Bi₂WO₆ nanomaterials are potential scaffold for the photocatalytic degradation of harmful antibiotics under visible-light irradiation.