Green synthesis of silver-titanium dioxide nanoparticles using chestnut extract for the preservation of leather artifacts

The deterioration of leather artifacts can be caused by exposure to light, pollutants, microbes, and oxidation. In this work, silver-titanium dioxide nanoparticles (Ag-TiO₂ NPs) were synthesized using chestnut extract as both a template and a reducing agent, providing UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity. The results indicated that the addition of chestnut extract and Ag significantly enhanced the UV light shielding capability of Ag-TiO₂ NPs by enhancing the light absorption efficiency, as well as reduced the band gap from 3.20 eV to 2.82 eV, and improved the self-cleaning capability as evidenced by an increase in Congo red (CR) dye degradation rate from 26 % to 55 %. Additionally, Ag-TiO₂ NPs also exhibited remarkable antibacterial activity, as evidenced by a significant increase in the inhibition zone against bacteria, as well as enhanced antioxidant capability with the DPPH free radical scavenging capability increased from 22 % to 88 %. After Ag-TiO₂ NPs treatment, there was no obvious change in the appearance of leather, while the antibacterial activity of leather was significantly increased. The Ag-TiO₂ NPs produced through a green approach could offer robust UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity to prevent the deterioration of leather artifacts, making a significant contribution to the long-term preservation of cultural heritage.