One-Step construction of Polyimide/NH2-UiO-66 heterojunction for enhanced photocatalytic degradation of sulfonamides.

Photocatalysis treatment is a promising technology to eliminate water pollutants. Herein, we constructed polyimide/NH2-UiO-66 composites (PUs) through a facile one-step solvothermal method for the photocatalytic degradation of sulfonamides. The optimized photocatalyst PU1.5 was superior to the photocatalysts prepared through multi-step methods due to the more exposed (001) facets of polyimide and the better distribution of small NH2-UiO-66 particles. PU1.5 showed the highest photocatalytic activity, which was 9.5 and 92.0 times higher than that of polyimide and NH2-UiO-66. Such improvement was attributed to the improved carrier separation efficiency resulted from direct Z-scheme heterojunction. The probable degradation pathway of sulfathiazole was proposed by the LC-MS/MS and Density Functional Theory (DFT) calculation. Furthermore, the reduced toxicity and the little antibacterial activity of intermediates was investigated by the Quantitative Structure-Activity Relationship (QSAR) analysis and the residual antibiotic activity experiment. The study might provide a new strategy for designing composite photocatalyst to achieve efficient removal of pollutants.