A π-π composited photocatalyst of aminobenzaldehyde and graphitic carbon nitride for photocatalytic elimination of antibiotics.

In order to improve the photocatalytic performance of graphitic carbon nitride (GCN), a composite photocatalyst of aminobenzaldehyde (ABA) modified GCN (ABA/GCN) was prepared through facile π-π stacking approach. Characterization results demonstrated that introduction of ABA could widen absorption of visible light and decrease the recombination of photogenerated charges. The composite photocatalyst could completely degrade moxifloxacin (MOX, 20 mg L^-1) under 80 min visible light irradiation, and the apparent rate constant is 2.4 times higher than that of the GCN. We further optimized the reaction conditions through studying the effects of pH value, photocatalyst dosage and MOX concentration on the activity. The modified photocatalyst presented high stability, durability and photocatalytic universality, as well as good potential in practical application. On basis of determined band structure and main active species, we proposed a possible photocatalytic mechanism. This work provides a possible strategy to enhance the photocatalytic performance through rational design of aromatic guest modified GCN.