Insight into the boosted ZEN degradation over defective Bi2WO6 ultrathin layers: ROS-mediated mechanism and application in corn oil

Abstract

Establishing an effective and sustainable strategy for zearalenone (ZEN) degradation is of great significance to agricultural development and food safety. Herein, more than 98 % of ZEN (2 ppm) was photocatalytic degraded within 90 min over the oxygen-deficient Bi₂WO₆ ultrathin layers (BWO-U), along with the sharp elimination of biotoxicity to GES-1 cells. Theoretical calculations and characterizations revealed the ultrathin structure and oxygen vacancies endowed BWO-U with strengthened photoelectrochemical activity and O₂-adsorption capacity, facilitating the generation of •O₂^- and ¹O₂ which play decisive roles in ZEN degradation. Furthermore, a possible mechanism was proposed based on nine intermediates identified via LC-MS, including the steps of cis-trans isomerization, oxidation and cleavage. Eventually, the method also exhibited immense potential in reducing ZEN-contamination in corn oil, and made no significant impact on the quality of corn oil. This work might provide a feasible strategy to mitigate ZEN-contamination and cast a new light on the ROS-mediated mechanism.

Keywords: Bi(2)WO(6); Photocatalysis; Reactive oxygen species; Zearalenone.