Antibacterial, photocatalytic, and enhanced glass by surface sol–gel SiO2 coating mixed with crystalline-Ag@P25

Conventional glass has limitations in mechanical strength and impact resistance and lacks antibacterial and photocatalytic functionalities, restricting its application in high-demand fields. In this study, a multifunctional glass surface coating with antibacterial, photocatalytic, and reinforcement properties has been developed by mixing SiO₂ sol with crystalline-Ag@P25 nanopowders. The coating maintains high transparency and exhibits outstanding stability and durability. The flexural strength and impact resistance of the coated glass increase significantly by 92 MPa and 14%, respectively. Furthermore, the glass presents excellent photocatalytic performance (reaching 22.8% degradation rate of methylene blue) and more than 99.9% antibacterial efficiency. Additionally, Raman signal analysis has been used to assess the filling rate of microcrack tips on the glass surface by the coating, providing a nondestructive testing method. The Raman analysis indicates that the coating penetrates the cracks on the glass surface, with an unfilled depth of less than 1.3 µm among the 4.77 µm depth of the preindented defect. These findings provide new technical support for the development and application of functionalized glass materials.