Electrospun Membranes Anchored with g-C3N4/MoS2 for Highly Efficient Photocatalytic Degradation of Aflatoxin B1 under Visible Light

Abstract

The degradation of aflatoxin (AF) is a topic that always exists along with the food and feed industry. Photocatalytic degradation as an advanced oxidation technology has many benefits, including complete inorganic degradation, no secondary contamination, ease of activity under moderate conditions, and low cost compared with traditional physical, chemical, and biological strategies. However, photocatalysts are usually dispersed during photocatalytic reactions, resulting in energy and time consumption in the separation process. There is even a potential secondary pollution problem from the perspective of food safety. In this regard, three electrospun membranes anchored with g-C3N4/MoS2 composites were prepared for highly efficient photocatalytic degradation of aflatoxin B1 (AFB1) under visible light. These photocatalytic membranes were characterized by XRD, SEM, TEM, FTIR, and XPS. The factors influencing the degradation efficiency of AFB1, including pH values and initial concentrations, were also probed. The three kinds of photocatalytic membranes all exhibited excellent ability to degrade AFB1. Among them, the photocatalytic degradation efficiency of the photocatalytic membranes prepared by the coaxial methods reached 96.8%. The experiment is with an initial concentration of 0.5 μg/mL (500 PPb) after 60 min under visible light irradiation. The mechanism of degradation of AFB1 was also proposed based on active species trapping experiments. Moreover, the prepared photocatalytic membranes exhibited excellent photocatalytic activity even after five-fold use in the degradation of AFB1. These studies showed that electrospun membranes anchored with g-C3N4/MoS2 composites have a high photocatalytic ability which is easily removed from the reacted medium for reuse. Thereby, our study offers a highly effective, economical, and green solution for AFB1 degradation in the foodstuff for practical application.

Advanced Electrospinning Technology Applied to Polymer-Based Sensors in Energy and Environmental Applications

“…Regarding the photocatalytic promotion mechanism of heterojunctions, the most recent research indicates that it can be explained through band theory. Taking g-C 3 N 4 /MoS 2 composite nanofiber photocatalyst as an example [ 108 ], under visible light irradiation, g-C 3 N 4 / MoS 2 on PAN electrospun film is simultaneously excited, generating photo-induced electrons and holes. It is known that the conduction band of g-C 3 N 4 is higher than that of MoS 2 , and the valence band of MoS 2 is lower than that of g-C 3 N 4 , as shown in Figure 10 c. The photoelectrons generated in g-C 3 N 4 transfer from its conduction band to the conduction band of MoS 2 , while the photo-induced holes generated in MoS 2 transfer from the valence band to the g-C 3 N 4 valence band, causing a large number of photoelectrons to gather in the conduction band of MoS 2 .…”

“…Copyright 2023, reproduced with permission from Elsevier. ( c ) Schematic diagram of a photocatalytic mechanism for degradation of the polymer and two-dimensional composite electrospun films [ 108 ]. Copyright 2023, reproduced with permission from MDPI.…”

“…Regarding the photocatalytic promotion mechanism of heterojunctions, the most recent research indicates that it can be explained through band theory. Taking g-C 3 N 4 /MoS 2 composite nanofiber photocatalyst as an example [108], under visible light irradiation, g-C 3 N 4 / MoS 2 on PAN electrospun film is simultaneously excited, generating photo-induced electrons and holes. It is known that the conduction band of g-C 3 N 4 is higher than that of MoS 2 , and the valence band of MoS 2 is lower than that of g-C 3 N 4 , as shown in Figure 10c.…”

Efficient Inhibition of Aspergillus flavus to Reduce Aflatoxin Contamination on Peanuts over Ag-Loaded Titanium Dioxide

“…Peanuts, with rich nutrients and health value, are a type of important oil crop [ 5 ], but they are susceptible to aflatoxin contamination. Aflatoxins, with high toxicity, teratogenicity, and carcinogenicity, have been regarded as the most toxic mycotoxins found in food and agri-food [ 6 , 7 , 8 ], which not only threaten human health, but also can lead to huge economic losses [ 9 , 10 , 11 , 12 , 13 ]. Aflatoxins are secondary metabolites, mainly produced by Aspergillus flavus (A. flavus) in food and agri-food, especially peanuts and corn [ 14 , 15 ].…”