Solvothermally grown BiOCl catalyst for photodegradation of cationic dye and fluoroquinolone-based antibiotics

A BiOCl catalyst was prepared via a green solvothermal method without using any surfactant or capping agent. The prepared BiOCl showed a uniform spherical morphology of about 60 nm with an energy band gap of 3.58 eV. Photoluminescence (PL) spectrum of BiOCl (λ_excitation = 310 nm) showed the first excitonic peak (near band edge emission peak) at 348 nm indicating the highly crystalline nature of the synthesized catalyst. The BiOCl photocatalyst showed the tetragonal crystal structure with the enhanced photocatalytic performance of 99% toward degradation of Rhodamine B (RhB) dye and three antibiotics, namely, ofloxacin (OFL), norfloxacin (NOR), and ciprofloxacin (CIP) under UV light irradiation. The photocatalytic degradation reaction of each pollutant follows the first-order kinetics with a high rate constant of about 0.0336 min⁻¹. Both electron and hole are the main reactive species involved in degradation of the pollutants. The prepared BiOCl retains its photocatalytic performance even after five cycles of use. The BiOCl catalyst has a high potential for photodegradation of cationic dye and fluoroquinolone antibiotics present in wastewater.