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The present study aimed to investigate the photodegradation of ibuprofen (IPF) by using black N–TiO 2 under visible LED illumination. The as-synthesized black N–TiO 2 nanoparticles were characterized by field emission scanning electron microscope (FESEM) equipped with energy dispersive X-ray spectrometer (EDS) detector, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), UV visible diffuse reflectance spectroscopy (UV-DRS), and Brunauer–Emmett–Teller (BET) techniques. The potential photocatalytic activity of the synthesized nanoparticles was assessed by degradation and mineralization of IPF under visible LED light irradiation. Compared to N–TiO 2 , the black N–TiO 2 exhibited higher degradation (96%) and mineralization (81%) efficiency for IPF under selected operational conditions. We observed that codoping of N and Ti3+ narrowed the band gap (2.1 eV) and decreased the recombination of photogenerated carriers. Pseudo-first order kinetic model was best fitted with the experimental results (R2 > 0.99 for different IPF concentrations). Radical-scavenging tests showed that hydroxyl radicals (•OH), holes (h+), and superoxide radicals (•O 2 −) are involved in the photocatalytic degradation of IPF, however •OH and •O 2 − played more important roles. The energy consumption of the system for different initial IPF concentrations was around 16.6–38.7 kWh/m3, indicating that the LED-black N–TiO 2 process is energy-efficient. The results revealed that the photocatalytic activity of the black N–TiO 2 is not changed much, even after 5 cycles, demonstrating its excellent photocatalytic stability and reusability. According to the findings, LED-black N–TiO 2 process has the potential to be applied for facile removal of contaminants of emerging concern (CECs) such as IPF from water resources. Image 1 • Black N–TiO 2 nanoparticles were prepared through facile combined impregnation method and NaBH 4 reduction. • Black N–TiO 2 nanoparticles exhibited outstanding catalytic performance and superior stability. • Co-doping of Ti3+ and N boosted light absorption and promoted separation-transport process of charge carriers. • Mechanistic analysis revealed differences in involvement of reactive species. • Lower EEO value meant less energy consumption under visible LED light irradiation. [ABSTRACT FROM AUTHOR]