Highly efficient g-C3N4 catalysts derived from various precursors for aflatoxin B1 degradation under visible light

Abstract

Aflatoxin B1 (AFB1), a mycotoxin commonly found in foodstuffs, poses significant health risks when ingested through contaminated food sources. Therefore, it is imperative to devise a safe and efficient method for AFB1 degradation. Graphitic carbon nitride (g-C₃N₄) stands out as an exceptionally stable, non-toxic, and economical photocatalyst, which is widely used in photocatalysis. In this study, we explored the photocatalytic performance of four g-C₃N₄ catalysts derived from different precursors (dicyandiamide (D-CN), melamine (M-CN), thiourea (T-CN), and urea (U-CN)) in AFB1 degradation under visible light. Notably, the U-CN catalyst displayed an impressive degradation rate of 93.5% for AFB1 within 30 min, outperforming M-CN (82.5%), T-CN (78.5%), and D-CN (46.2%). This superior performance is attributed to its inherent porous structure, enlarged specific surface area, and reduced electron–hole pairs’ recombination rate. Additionally, our investigation identified ˙O₂⁻ as the primary active species in AFB1 degradation. Furthermore, we explored the degradation pathway of AFB1 and its associated inactivation mechanism mediated by the U-CN catalyst. This work provides a theoretical foundation for developing highly efficient photocatalysts in AFB1 degradation.