MOF-derived La-ZnFe2O4@Fe3O4@carbon magnetic hybrid composite as a highly efficient and recyclable photocatalyst for mycotoxins degradation

During the planting, storage, or feeding stages, foodstuffs can be easily polluted by mycotoxins such as aflatoxin B1, patulin and zearalenone, which are produced by pathogenic microorganisms. Therefore, the removal of these mycotoxins constitutes an active area of research. Herein, we used an Fe/Zn metal-organic framework (MOF) as a precursor to fabricate a novel La-ZnFe2O4@Fe3O4@carbon magnetic hybrid composite via a simple absorption-pyrolysis method and explored its photocatalytic performance in the degradation of aflatoxin B1, patulin, and zearalenone. La-ZnFe2O4@Fe3O4@carbon can effectively degrade 98.37% of aflatoxin B1, outperforming Fe3O4@carbon (69.57%) and ZnFe2O4@Fe3O4@carbon (91.39%). Moreover, La-ZnFe2O4@Fe3O4@carbon exhibits superior stability and excellent photocatalytic activity for the degradation of patulin (97.35%) and zearalenone (98.52%). Transient photocurrent response measurements reveal that the La doping and the combination with ZnFe2O4 highly promote the separation of photoinduced electron-hole pairs on Fe3O4@carbon. An electron spin resonance analysis suggests that center dot OH and center dot O-2 are the main active radicals during the photodegradation process. Thus, a plausible photodegradation pathway for the degradation of mycotoxins produced by pathogenic microorganisms is proposed.

Automated summary

During the planting, storage, or feeding stages, foodstuffs can be easily polluted by mycotoxins such as aflatoxin B1, patulin and zearalenone. Therefore, the removal of these mycotoxins constitutes an active area of research. Herein, a novel La-ZnFe2O4@Fe3O4@carbon magnetic hybrid composite was fabricated and its photocatalytic performance in the degradation of mycotoxins was explored. The composite showed superior degradation efficiency for aflatoxin B1, patulin, and zearalenone, and a plausible photodegradation pathway was proposed.