High-performance PVA composite films reinforced with MoS2-Ag-NCQD nanohybrids for enhanced oxygen barrier, UV shielding, and sustainable meat preservation.

Abstract

To meet the growing demand for sustainable and eco-friendly food-packaging solutions, nanomaterials offer innovative approaches for mitigating microbial spoilage, particularly in the preservation of meat. Research has focused on the development of degradable packaging with strong antibacterial properties to enhance shelf life and ensure food safety. In this study, few-layer water-dispersible molybdenum disulfide (M) nanosheets were fabricated using ultrasonic-assisted liquid exfoliation. The nanosheets were subsequently combined with silver-doped, nitrogen-functionalized carbon quantum dots (Ag-NCQDs) to create M-Ag-NCQDs with varying loading concentrations. We synthesized and characterized poly(vinyl alcohol) (PVA)/M-Ag-NCQDs nanostructured films to assess their multifunctional properties, focusing on their oxygen-barrier efficiency, antimicrobial activity, ultraviolet (UV) shielding, and potential applications in storage testing. The incorporation of Ag-NCQDs into the PVA matrix at concentrations between 0.5 and 5.0 wt% resulted in a significantly improved film performance. Notably, the PVA/M-Ag-NCQDs (5) formulation exhibited remarkable enhancements with a 71.8% increase in tensile strength, 99.7% UV-A shielding effectiveness, 16.2% increase in crystallinity, and 99.9% improvement in the oxygen-transmission rate. Additionally, the introduction of the M-Ag-NCQDs led to a 44% increase in the water contact angle, indicating excellent hydrophobicity. In practical applications, these films were used to wrap fresh chicken breast stored at 6 °C for 12 days, demonstrating superior quality preservation compared with conventional packaging. These findings highlight the potential of PVA/M-Ag-NCQDs nanostructured materials as advanced sustainable packaging materials that provide enhanced barrier, antimicrobial, and UV-protective characteristics and exhibit the potential for cosmetic applications.