Novel ZnO@NPC core–shell polyhedral heterostructures derived from ZIF-8 with enhanced photocatalytic performance for aflatoxin B1 degradation

Abstract

Aflatoxin is one of the most toxic mycotoxins and causes server threaten to human health and food safety issues. It is crucial to develop efficient materials to remove and degrade aflatoxins. In this work, we adopted PVP modified ZIF-8 as precursor to prepare novel ZnO@NPC core–shell heterostructures (NPC is N-doped porous carbon) via “pyrolysis-in situ transformation-pyrolysis” strategy and used it as catalyst for degradation of aflatoxin B1 (AFB1). Various technologies were adopted to characterize to the structures and properties of the catalyst, such as XRD, SEM, BET, and TEM. The results show that the coating of N-doped porous carbon on ZnO can extend its light absorption wavelength to 800 nm, enhancing its photocatalytic activity for degradation of AFB1 (94.8%). The synergetic effect of high absorption capacity on N-doped porous carbon and excellent photocatalytic activity on ZnO was proven to contribute high degradation performance of ZnO@NPC. ZnO@NPC also shows excellent reparation and reusability. The photocatalytic activity of ZnO@NPC reduces only 1.71% after five repeated cycles. The developed ZnO@NPC may bring a promising solution for toxin degradation.