Photocatalytic degradation and transformation of pharmaceuticals using exfoliated metal-free g-C3N4

was synthesized from dicyandiamide at 550°C and exfoliated at 500 °C for 1-3 h in an ambient atmosphere. The structural, textural, and electronic properties of the prepared materials were evaluated. Graphitic carbon nitride exfoliated for 2 h provided the best photocatalytic degradation efficiencies (>95%) for both ofloxacin and diclofenac and approximately 80% for caffeine, determined for 120 min under irradiation at 420 nm. The pharmaceuticals were degraded, and their intermediate degradation products were investigated using liquid chromatography combined with high-resolution tandem mass spectrometry. The successful identification of the main degradation products allowed us to propose transformation pathways for the studied pharmaceuticals.