Porous 0D/3D NiCo2O4/g-C3N4 accelerate emerging pollutant degradation in PMS/vis system: Degradation mechanism, pathway and toxicity assessment

Herein, porous 0D/3D NiCo2O4/g-C3N4 catalyst was precisely designed to degrade carbamazepine (CBZ) and effluent organic matter (EfOM) in real secondary effluent. The physical structure, optical property, photovoltaic and photo(electro)chemical properties were explored in detail. CBZ was almost completely removed within 10 min in PMS/vis system, and TOC removal efficiencies for CBZ and raw secondary effluent from wastewater treatment plant (WWTP) were 53.0% and 43.0%, respectively. Also, the effect of various conditions (PMS concentration, pH value, catalysts dosage, CBZ concentration and type of anions) was evaluated using pollutant degradation experiments. Cyclic degradation experiment and characterization results of fresh and used photocatalyst confirmed the extremely high stability of NiCo2O4/g-C3N4. Additionally, a series of characterizations were applied to deeply explore reactive oxidation species (O2−, SO4−, OH and 1O2) generation and consumption process. Finally, the degradation pathways of CBZ were proposed and corresponding toxicity of products was analyzed by quantitative structure activity relationship (QSAR).