A plasmonic Z-scheme Ag@AgCl/PDI photocatalyst for the efficient elimination of organic pollutants, antibiotic resistant bacteria and antibiotic resistance genes

Herein, a plasmonic Z-scheme Ag@AgCl/PDI photocatalyst was successfully synthesized by an in-situ deposition-photoreduction method. The loading of Ag@AgCl nanoparticles could improve the light absorption ability of self-assembled perylene diimide (SA-PDI) via the SPR effect. Ag nanoparticles as electron traps could effectively capture photogenerated electrons on the conduction band of SA-PDI, while the Schottky barrier formed by Ag0 could promote SPR-excited electrons to transfer from Ag to AgCl, further accelerating the charge separation. Besides, more reactive species (•O2-, 1O2, h+ and •OH) could be produced to enhance the oxidation capacity of composite. Therefore, compared with SA-PDI, Ag@AgCl/PDI exhibited more remarkable visible-light photocatalytic performance for the elimination of organic pollutants, antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). The degradation rates of optimum Ag@AgCl/PDI-3% towards phenol, bisphenol A, sulfadimethoxine and ofloxacin were approximately 5.7, 4.0, 3.2 and 10.0 times higher than those of SA-PDI, respectively. Meanwhile, Ag@AgCl/PDI-3% killed all sulfonamide ARB within 2 h and inactived 99.6% of sulfonamide ARGs (sul1) within 8 h, while SA-PDI only removed 49.4% of ARB and 49.9% of sul1. This study could provide a new strategy to design high-efficiency PDI-based photocatalysts for environmental remediation.