3.4.3. Radical Scavenging Experiment

The dominant active species involved in the photodegradation of diclofenac drug was identified via radical scavenging experiments. Each scavenger (5 mL) was separately mixed with the drug solution, and the whole catalytic process was repeated under identical conditions. The scavengers used were isopropyl alcohol (IPA, 0.01 M), triethanolamine (TEOA, 0.01 M) and benzoquinone (BQ, 0.01 M) to quench hydroxyl radicals (OH^•), holes (h⁺), and superoxide anions (^•O₂⁻²), respectively.