Synthesis and application of UiO-66-NO2@Ag/AgCl nanocomposite as photocatalysts for water remediation

Photocatalytic degradation of organic pollutants in water represents a highly promising strategy for environmental remediation. However, conventional photocatalysts are hampered by their inefficient employment of visible light energy and the propensity of photoinduced charge carriers to undergo recombination. To overcome these limitations, Z-scheme photocatalyst UiO-66-NO 2 @ Ag/AgCl (UiO@Ag-X, where X denotes the Ag/AgCl content) composites were designed and prepared. The crystal structure, morphology, photocatalytic performance, light absorption capacity, and carrier separation efficiency were systematically tested. Optical and electrochemical measurements revealed that the incorporation of Ag/AgCl enhanced the segregation and transfer efficiency of charge, which is crucial for boosting photocatalytic activity. These improvements directly contributed to the enhanced degradation efficiency observed in subsequent experiments. In experiments using methyl violet (MV) as the model pollutant, the photocatalytic degradation performance of UiO@Ag-X samples was evaluated. Among these samples, UiO@Ag-50 achieved a remarkable degradation efficiency under light irradiation. Moreover, the corresponding kinetic rate constant was about 0.04724 min -1 , which was higher than that of UiO-66-NO 2 . Quenching experiments were employed to investigate the mechanisms related to photocatalysis. The results show that hydroxyl radicals play an important role in the degradation of MV.