Enhanced photocatalytic performance of Z-scheme N-doped Ag2CO3/GO (AGON) for microcystin-LR remediation under visible light

Abstract A novel Z-scheme Ag2CO3-NG heterojunction photocatalyst by employing N-doped graphene (NG) was successfully synthesized with enhanced photocatalytic activity for microcystin-LR (MC-LR) degradation. Characterization results suggested that doping of N can promote the nucleation and crystallization of Ag2CO3. Photocatalytic tests showed that Ag2CO3-NG with 30 wt.% N-participation (AGON/1–30) showed the best photocatalytic performance under visible-light irradiation, which could remove MC-LR in 7.5 min, superior to Ag2CO3-GO composite. Multiple factors including dosage, pH value, MC-LR concentration, H2O2, and the coexistence of Microcystis aeruginosa were studied to reveal the environmental impact on MC-LR degradation. Results showed that ·OH, ·O2−, as well as ·CO3− were the main ROSs in MC-LR degradation. The excellent reusability and stability of AGON/1–30 were proved through five consecutive cycles of degradation. Therefore, the Z-scheme Ag2CO3-NG heterojunction photocatalyst is a promising technique for MC-LR remediation.