Z-scheme heterojunction g-C3N4-TiO2 reinforced chitosan/poly(vinyl alcohol) film: Efficient and recyclable for fruit packaging

Int J Biol Macromol. 2024 May;268(Pt 1):131627. doi: 10.1016/j.ijbiomac.2024.131627. Epub 2024 Apr 16.

Abstract

Nanoparticles-loaded bio-based polymers have emerged as a sustainable substitute to traditional oil-based packaging materials, addressing the challenges of limited recyclability and significant environmental impact. However, the functionality and efficiency of nanoparticles have a significant impact on the application of bio-based composite films. Herein, graphitic carbon nitride (g-C3N4) and titanium dioxide (TiO2) coupled photocatalyst (g-C3N4-TiO2) was prepared by one-step calcination and introduced into chitosan (CS) and polyvinyl alcohol (PVA) solution to fabricate g-C3N4-TiO2/CS/PVA green renewable composite film via solution casting method. The results demonstrated the successful preparation of a Z-scheme heterojunction g-C3N4-TiO2 with exceptional photocatalytic activity. Furthermore, the incorporation of heterojunction enhanced mechanical properties, water barrier, and ultraviolet (UV) resistance properties of the fresh-keeping film. The g-C3N4-TiO2/CS/PVA composite film exhibited superior photocatalytic antibacterial preservation efficacy on strawberries under LED light, with a prolonged preservation time of up to 120 h, when compared to other films such as polyethylene (PE), CS/PVA, g-C3N4/CS/PVA, and TiO2/CS/PVA. In addition, the composite film has good recyclability and renewability. This work is expected to have great potential for low-cost fruit preservation and sustainable packaging, which also contributes to environmental protection.

Keywords: Bio-based polymers; Green renewable; Photocatalytic; Sustainable packaging; Z-scheme heterojunction.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Catalysis
  • Chitosan* / chemistry
  • Food Packaging* / methods
  • Fruit / chemistry
  • Graphite* / chemistry
  • Nitrogen Compounds / chemistry
  • Polyvinyl Alcohol* / chemistry
  • Titanium* / chemistry

Substances

  • titanium dioxide
  • graphitic carbon nitride