Preparation of Fe/N-MWCNT as highly efficient catalyst for degradation of pharmaceutical ibuprofen

Carbon nanostructures are emerging as advanced functional materials for pharmaceutical removal from wastewater. In this study, N-doped multi-walled carbon nanotube (N-MWCNT) hybrids were synthesized via CVD using an Fe catalyst at 750 °C for 1–3 h to degrade ibuprofen (IBF). The 3-hour sample (CN3) showed the best performance, with a high surface area (205.4 m 2 /g) and pore volume (0.824 cm 3 /g), achieving 92% IBF removal under 300 W VL irradiation for 60 min. Increasing CN3 dosage from 10 to 40 mg further enhanced degradation. Stability tests revealed only a 3% decline in efficiency after four cycles, indicating excellent durability. Scavenger and EPR analyses indicate O 2 • − is the dominant oxidizing species, with •OH contributing secondarily under visible-light irradiation. These findings highlight synthesis conditions’ critical role in photocatalytic activity.