Optimization of Ag single atom dispersed graphitic carbon nitride for enhanced catalytic performance in the degradation of rhodamine B and tetracycline

Owing to their unique electronic structure, single atom (SA) catalysts exhibit high activity and selectivity in the photocatalytic elimination of organic compounds. Herein, to improve the intrinsic activity of Ag SAs, Ag SA/g-C3N4 was synthesized via a one-step photocatalytic immobilization strategy. Ag SA/g-C3N4 exhibited excellent photocatalytic performance in removing organic pollutants, achieving degradation efficiencies of 93.49% and 64.29% for rhodamine B (RhB) and tetracycline (TC), respectively, under visible-light irradiation for 180 min. This enhanced photocatalytic activity stemmed from the synergistic electronic interaction between Ag SA/g-C3N4 and RhB, whose photocatalytic degradation contributed to immobilize the Ag SAs and construct electron migration channels. This electronic structure suppressed the aggregation of Ag SAs. Ag nanoparticles could retain a small particle size of 2.79 nm after being recycled thrice. This study provides an innovative method for the immobilization of Ag SAs to improve their photocatalytic activity in the removal of RhB and TC.