Amoxicillin Photodegradation Under Visible Light Catalyzed By Metal-Free Carbon Nitride: An Investigation Of The Influence Of The Structural Defects

Herein, the structural defects of metal-free polymeric carbon nitrides were controlled by making use of different precursors in their syntheses, i.e. melamine (CN-M) and thiourea (CN-T), as well as a 1:1 mixture of them (CN-1M:1 T). By controlling the structural defects, the electronic, morphological and chemical properties were modified. Additionally, the activities of synthesized PCNs were evaluated for amoxicillin photodegradation under visible light irradiation (16 mW cm(-2)). The results of photocatalytic tests showed that CN-T material has better efficiency (100 % removal within 48 h), which is directly related to the greater number of defects present in its structure with consequent improvement of electron-hole pairs separation efficiency. The CN-T material showed excellent stability with only 13 % decrease in its photocatalytic activity after the third cycle. A mechanism for amoxicillin degradation by CN-T was proposed based on the ESI-MS and the in situ EPR allied with spin trapping method investigations.