Inactivation of Microcystis aeruginosa using piezoelectric T-BaTiO3/Ag3PO4-PVDF composite photocatalyst: Characterization, performance and mechanism

Abstract

To mitigate the profound impact of Microcystis aeruginosa algal bloom outbreaks on aquatic ecosystems and human health, a piezoelectric T-BaTiO3/Ag3PO4-PVDF composite photocatalyst (T-BTO/AP-PVDF) was successfully synthesized in this study. The catalyst inactivated 97.12% of Microcystis aeruginosa within 4 h by the combined effect of ultrasound and sunlight, and the inactivation rate remained above 88% after five cycles of reuse, which exhibits excellent inactivation effectiveness and stability. Under the conditions of piezo-photocatalytic, the analysis of the physiological properties of algal cells showed that T-BTO/AP-PVDF produced a large amount of •OH, which were active species that could effectively inactivate the algal cells and promote the degradation of organic matter, thus preventing the occurrence of secondary pollution. The composite photocatalysts were characterized using XRD, SEM, XPS, FTIR, PFM, and WCA. Combined with the results of quenching experiments, possible mechanisms for the inactivation of Microcystis aeruginosa by T-BTO/AP-PVDF were proposed. The application results in actual water bodies further proved that T-BTO/AP-PVDF is a new method for effectively inhibiting cyanobacterial bloom outbreaks and shows promising potential for application.