*3.4. Photocatalytic Experiments*

To test the activity of the synthesized catalysts in the photodegradation process of ciprofloxacin and levofloxacin, a solar simulator composed of three white annular bulbs with a total irradiation power of 90 watts was used. In the case of ciprofloxacin, <sup>a</sup> <sup>2</sup> <sup>×</sup> <sup>10</sup>−<sup>5</sup> <sup>M</sup> solution was prepared, while for levofloxacin the concentration used was 10−<sup>5</sup> M. Next, the desired catalyst was added, the amount of which also depended on the antibiotic used. After adding the catalyst and adjusting the pH to 7, the system was kept in the dark for 30 min to allow the system to reach adsorption–desorption equilibrium. Then, a small amount of H2O<sup>2</sup> (2 mL, 0.005%) was added, and additional oxygen was provided to the system by constantly bubbling air into the reaction mixture. The white bulbs were then turned on and the photocatalytic system was maintained with constant agitation and irradiation. The reaction was monitored for a period of 180 min and photodegradation was followed by taking aliquots every 15 min. After filtering the aliquots with Whatman® Puradisc 13 (Clifton, NJ, USA) disposable syringe filters, the samples were immediately analyzed at room temperature with a Perkin Elmer Lambda 35 UV-vis spectrophotometer (San José, CA, USA).
