Fabrication of Mn2+–Zr4+@MgFe12O19 for photocatalytic degradation of enrofloxacin antibiotic

Antibiotic contamination in water bodies has become a critical environmental issue due to its persistence, bioaccumulation, and resistance to conventional wastewater treatment methods. This study reports the synthesis, characterization, and photocatalytic application of Mn2+–Zr4+-doped magnesium (Mg) M-type hexaferrites for degrading enrofloxacin (ENF) antibiotic in veterinary wastewater. Six samples with varying doping concentrations (x = 0.00–0.1, y = 0.00–1.00) were synthesized using the sol–gel auto-combustion method. Comprehensive structural, morphological, and optical analyses confirmed successful incorporation of manganese and zirconium ions into the M-type magnesium hexaferrite matrix. The crystal sizes of the synthesized samples decreased from 84.2 to 75.9 nm, while the unit cell volume increased from 685.45 to 701.85 Å3 with increasing doping concentrations. The bandgap energy was reduced from 2.02 to 1.79 eV. The optimized composition (Mg0.92Zr0.08Fe11.2Mn0.8O19) demonstrated the highest degradation efficiency by way of achieving 95.5% ENF removal with a rate constant of 0.036 min−1 in only 80 min. These results highlight the remarkable potential of Mn2+–Zr4+-doped magnesium M-type hexaferrites as efficient and sustainable photocatalysts for environmental remediation applications.