Engineering dual defects onto graphitic carbon nitride nanosheets enables outstanding performance for photodegradation of microcystin-LR.

Algal blooms in eutrophic water often produce microcystins, which can lead to multi-organ dysfunction and even mortality in many organisms. Therefore, the elimination of microcystins in water is an urgent issue that needs to be addressed. Herein, we develop a dual defect engineering strategy to construct graphite-like carbon nitride with N vacancies and -CN groups (NgCN) nanosheets for microcystin-LR (MC-LR) photodegradation. According to our theoretical calculations and actual findings, the NgCN nanosheets enhanced recyclability for the removal of MC-LR while also demonstrating outstanding photocatalytic efficacy, significantly surpassing the graphite-like carbon nitride under visible light, which is ascribed to efficient charge separation as well as narrowing the bandgap. Impressively, the water quality after photodegradation has been proven to be safe based on International Organization for Standardization (ISO) standards. This finding provides meaningful insights into understanding the relationship between defect engineering and photodegradation performance to design photocatalytic materials with higher activity for environmental remediation.