Solar light induced antibacterial performance of TiO ₂ crystallized glass ceramics

Abstract This work investigates the antibacterial potential of TiO ₂ ‐based glass‐ceramic. A glass of TiO ₂ microcrystals embedded in glass matrix of BaO‐TiO ₂ ‐B ₂ O ₃ was obtained by melt quench method followed by controlled heat treatment at the 650°C for 3 hours. Crystallization of anatase phase of TiO ₂ was confirmed by X‐ray diffraction. UV ‐visible absorbance and photoluminescence were also recorded. Interestingly band gap of TiO ₂ glass‐ceramic (crystallized glass) was found to be 2.9 eV . Crystallized glass showed excellent antibacterial property against Escherichia coli in both forms (powder and plate). More than 90% of disinfection was achieved by photocatalytic TiO ₂ glass‐ceramic surface within one hour of sunlight exposure, which was significantly higher than as‐quenched glass surface and TiO ₂ glass‐ceramic surface under dark. Intracellular reactive oxygen species ( ROS ) intensity of bacterial cells in the presence of crystallized glass was almost three times higher than the control and as‐quenched glass under light. Higher production of ROS is major factor for bacterial degradation on crystallized glass surface.