A multi-functional α-Fe2O3/g-C3N4/chitosan nanocomposite film with photodynamic antibacterial behavior for long-term preservation of perishable products

This study presents an innovative nanocomposite film with multiple synergistic sterilization modes, which aims to enhance the freshness of fruits and reduce wastage by capitalizing on the availability of sunlight. In detail, α-Fe 2 O 3 /g-C 3 N 4 (FOCN) nanocomposite with excellent visible-light-harvesting ability and photodynamic antibacterial activity was fabricated, which was then filled within a chitosan (CS) matrix, resulting in a novel antibacterial film for food preservation. The obtained α-Fe 2 O 3 /g-C 3 N 4 /chitosan (FOCN/CS) film exhibited impressive antibacterial activities, with sterilizing rate of 99.7 % ± 0.6 % against Escherichia coli ( E. coli ) and 97.6 % ± 0.4 % against Staphylococcus aureus ( S. aureus ) with short processing time (10 min) under visible light illumination. Based on this, the FOCN/CS film demonstrated excellent food preservation performance, which significantly prolonged the shelf life of strawberries, baby bok choy and pork. Such satisfactory preservation ability originates from the synergistic effect of α-Fe 2 O 3 and g-C 3 N 4 , which formed S-type heterojunction and bestow the FOCN/CS film with superior photodynamic antibacterial activity. Therefore, the film provides a novel microbiological control barrier for food preservation, with the potential to effectively reduce microbiologically induced food spoilage problems.