Visible Light‐Driven Degradation of Levofloxacin by Europium‐Doped Zinc Bismuth Spinel Oxide

ABSTRACT Semiconductor photocatalysis is a widely employed strategy for the effective removal of pollutants from wastewater. Among various semiconductors, AB 2 X 4 ‐type spinel compounds have appeared as a promising class of advanced catalytic materials for drug degradation. In the present study, europium‐doped zinc bismuth spinel oxides were synthesized via a hydrothermal method. Europium doping introduces lattice defects and reduces the band gap, thereby enhancing visible‐light absorption and improving photocatalytic performance. The synthesized spinel oxides were characterized by FTIR, UV–vis spectroscopy, SEM–EDX, and XRD analyses, which confirmed their structural and optical features. The photocatalytic activity was systematically investigated by varying key operational parameters, including irradiation time, solution pH, catalyst dosage, and initial drug concentration. The optical band gaps of the ZBO‐ and Eu‐doped ZBO catalysts were 2.73, 2.42, 2.22 and 2.38 eV, respectively, indicating a progressive narrowing of the band gap upon Eu doping. Optimization studies demonstrated that up to 93.39% levofloxacin (LVF) removal efficiency could be achieved using 0.5 g/L catalyst in a 10 ppm LVF solution at neutral pH (≈7) within 120 min under visible‐light irradiation.