Enhancement of AFB Removal Efficiency via Adsorption/Photocatalysis Synergy Using Surface-Modified Electrospun PCL-g-CN/CQDs Membranes.

Aflatoxin B (AFB) is a highly toxic mycotoxin produced by aspergillus species under specific conditions as secondary metabolites. In this study, types of PCL (Polycaprolactone) membranes anchored (or not) to g-CN/CQDs composites were prepared using electrospinning technology with (or without) the following surface modification treatment to remove AFB. These membranes and g-CN/CQDs composites were characterized by SEM, TEM, UV-vis, XRD, XPS and FTIR to analyze their physical and chemical properties. Among them, the modified PCL-g-CN/CQDs electrospun membranes exhibited an excellent ability to degrade AFB via synergistic effects of adsorption and photocatalysis, and the degradation rate of 0.5 μg/mL AFB solution was observed to be up to 96.88% in 30 min under visible light irradiation. Moreover, the modified PCL-g-CN/CQDs electrospun membranes could be removed directly after the reaction process without centrifugal or magnetic separation, and the regeneration was a green approach synchronized with the reaction under visible light avoiding physical or chemical treatment. The mechanism of adsorption by electrostatic attraction and hydrogen bonding interaction was revealed and the mechanism of photodegradation of AFB was also proposed based on active species trapping experiments. This study illuminated the highly synergic adsorption and photocatalytic AFB removal efficiency without side effects from the modified PCL-g-CN/CQDs electrospun membranes, thereby offering a continual and green solution to AFB removal in practical application.