Herein, we successfully fabricated transparent and highly flexible polyvinyl alcohol@ZnO:Ga3+ (PVA@ZnO:Ga3+) nanocomposites (NCs) films by simple solution casting method. Upon excitation at 266 nm, both the ZnO:Ga3+ nanoparticles (NPs) and the PVA@ZnO:Ga3+ NCs exhibit a prominent peak at 385 nm and a broad peak around 550 nm. The optimized PVA@ZnO:Ga3+ NCs demonstrated the most effective ultra violet (UV) blockage across the UV-A (99.99 %), UV-B (100 %) and UV-C (100 %) and high energy blue light HEBL (94.63 %). However, PVA alone absorbed <25 % of the light in all UV regions. Packaging of fresh cherry fruit with PVA@ZnO:Ga3+ (0.1 wt%) NCs enhanced the shelf-life up-to 15 days of storage under room temperature. These innovative NCs packaging films could provide a green, environment-friendly and antimicrobial system to combat the shorter shelf life of cherry fruit. The optimized NCs exhibited excellent shape recovery under pH conditions of 1, 7 and 13 and at a temperature of 70 °C, returning to its original shape within 120, 150, 160 and 6 sec, respectively. This emphasizes the NCs remarkable water-induced shape memory ability. Further, PVA@ZnO:Ga3+ NCs security ink offers strong anti-counterfeiting (AC) properties with UV luminescence and stability against UV exposure, aging and temperature effect. It adheres well to various substrates, ensuring long-term durability and resistance to replication. Overall, the results clearly show that ZnO:Ga3+ NPs hold great promise for applications in AC technology, UV blocking and the food packaging industry, thanks to their low cost, biocompatibility, flexibility and transparency.
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