Inactivation of harmful cyanobacteria by Ag/AgCl@ZIF-8 coating under visible light: Efficiency and its mechanisms

A novel floating photocatalyst was prepared by depositing Ag/AgCl@ZIF-8 on a sodium dodecyl benzene sulfonate modified sponge with a simple dip-coating method and was employed for the inactivation of harmful cyanobacteria for the first time. The effect of coated sponge on Microcystis aeruginosa under visible light was investigated and a possible mechanism was proposed. The results showed that the synthesized photocatalyst exhibited outstanding performance with a high removal efficiency of chlorophyll a reaching 98.5% after 4 h and revealed excellent stability under visible light. The superoxide radicals, holes and hydroxyl radicals played a crucial role, which causing the damage of cell wall and membrane, the bleaching of pigments, the collapse of superoxide dismutase and hydrogen peroxidase and other oxidation stress effects. Above all, Ag/AgCl@ZIF-8 sponge fabricated from this simple and cost-effective dip-coating method has a promising prospect for the removal of harmful cyanobacteria in eutrophic water bodies.