Efficient photocatalytic inactivation of Microcystis aeruginosa via self-floating Ag3VO4/BiVO4 hydrogel under visible light

In this work, a facile separation of self-floating Ag3VO4/BiVO4 hydrogel (ABVH) photocatalyst was constructed via the freeze-thaw method for the inactivation of Microcystis aeruginosa. The as-synthesized photocatalyst exhibited excellent photocatalytic performance, resulting in the degradation efficiency of chlorophyll a reaching approximately 99.6% within 4 h under visible light. The cell morphology, intracellular organic matter (IOM), extracellular organic matter (EOM), and antioxidant system were severely disrupted during the photocatalytic process. The inactivation mechanism could be ascribed to the ·OH and h+ generated by hydrogel photocatalyst under visible light irradiation. Furthermore, five repetitive experiments and cyclic compressive stress-strain tests demonstrated that the as-prepared hydrogel possessed excellent reusability and mechanical strength properties. Besides, the hydrogel photocatalyst showed excellent potential for the removal of M. aeruginosa in the presence of natural organic matter (NOM). Overall, the synthesized self-floating hydrogel photocatalyst may offer a novel insight into the control of harmful cyanobacterial blooms.