Polyimide composites modified by C.I. Pigment Green 8 with enhanced crystalline structure for efficient photo-Fenton oxidative degradation of tetracycline hydrochloride

Composite material (PGPI) of polyimide (PI) modified by C.I. Pigment Green 8 (PG8) were prepared by solid-phase thermal polycondensation, impregnation and thermal treatment. The introduction of PG8 enhanced the π-π stacked crystalline structure and the visible light absorption of PI. The photo-Fenton synergistic system can effectively increase the decomposition efficiency of H2O2, accelerate Fe2+/Fe3+ cycling and reduce the recombination of photogenerated carriers. The synergistic oxidative removal of TH (Tetracycline hydrochloride, 50 ppm) by PGPI after 40 min under visible-light irradiation was 95.1 %, which was significantly better than that of the photocatalysis alone (40.7 %) and the Fenton reaction alone (55.0 %).