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.
摘要：
纳米颗粒负载的生物基聚合物已成为传统油基包装材料的可持续替代品，解决可回收性有限和重大环境影响的挑战。然而,纳米粒子的功能性和效率对生物基复合膜的应用有显著影响。在这里，通过一步煅烧制备石墨碳氮化物（g-C3N4）和二氧化钛（TiO2）耦合光催化剂（g-C3N4-TiO2），并将其引入壳聚糖（CS）和聚乙烯醇（PVA）溶液中，通过溶液流延法制备g-C3N4-TiO2/CS/PVA绿色可再生复合膜。结果表明，成功制备了具有出色光催化活性的Z型异质结g-C3N4-TiO2。此外，异质结的掺入增强了机械性能，水屏障,保鲜膜的抗紫外线(UV)性能。g-C3N4-TiO2/CS/PVA复合膜在LED光下对草莓表现出优异的光催化抗菌保鲜效果,具有长达120小时的延长保存时间，与聚乙烯（PE）等其他薄膜相比，CS/PVA,g-C3N4/CS/PVA,和TiO2/CS/PVA。此外,复合薄膜具有良好的可回收性和可再生性。这项工作有望在低成本水果保鲜和可持续包装方面具有巨大潜力，这也有助于环境保护。
