Ultrahigh photoactivity of ZnO nanoparticles for decomposition of high‑concentration microcystin‑LR in water environment
Ultrahigh photoactivity of ZnO nanoparticles for decomposition of high‑concentration microcystin‑LR in water environment
Use of highly photoactive materials is critical for applicability of photocatalysis in large-scale water treatment facilities. Unfortunately, in a real setting, the performance of existing photocatalysts is not as good as expected. Therefore, finding a truly photoactive material is of great importance. Herein, ZnO nanoparticles prepared through a simple solid-state route at moderate temperatures in the absence of oxygen are demonstrated to be a suitable option for environmental photocatalysis. Within only 8 min of UVA irradiation at pH 6, the degradation efficiency for 2 mg/L of microcystin-LR using 0.5 g/L of ZnO synthesized at 350°C reaches as high as 97%. Hydroxyl radicals and valence band holes are found to be responsible for such a high degradation of microcystin-LR. The photocatalytic activity can also be maintained after six successive uses.