Sol–gel TiO2–SiO2 mixed oxides as dual-functional photocatalytic and Bioactive materials

Nanomaterials exhibit enhanced mechanical, electrochemical, electrical, catalytic, thermal, and optical properties relative to their individual nanoscale components. The TiO 2 –SiO 2 composite was prepared through a sol–gel process involving TTIP (0.0101 mol) and TEOS (0.0224 mol). The resulting TiO 2 and SiO 2 sols were mixed in a 1:1 ratio to form the TiO 2 –SiO 2 mixed oxide. The synthesized nanomaterial was characterized by state-of-the-art techniques to analyze various physicochemical properties of the TiO 2 –SiO 2 composite. UV–Vis was utilized to investigate electronic excitation behaviors. SEM provided insights into the surface morphology and structural features of TiO 2 –SiO 2 material, while EDX confirmed the elemental composition, including the presence of titanium (Ti), silicon (Si), and oxygen (O). FT-IR was conducted to identify functional groups, revealing characteristic bands corresponding to Ti–O, Ti–OH, O–H, Si–O, and Si–OH groups. Additionally, DSC and TGA were employed to examine thermal behavior, indicating heat flow transitions and mass loss patterns as a function of temperature. Similarly, to study the point of zero charge (pH pzc ) Rhodamine B (RhB) and Methylene Blue (MB) dye solutions were adjusted to different pH levels using 0.1 M HCl and 0.1 M NaOH, while maintaining constant experimental conditions and the pH pzc was found to be 6.4 for the composite. The catalytic and photocatalytic performances of the synthesized nanocomposite were evaluated through the degradation of Methylene Blue (MB) and Rhodamine B (RhB) dyes under light irradiation. The results demonstrated photocatalytic degradation efficiencies of approximately 92 % for RhB within 6 h and 70 % for MB within 5 h. In addition, the nanocomposite was evaluated for its biological activities, including α-glucosidase inhibition, and cytotoxicity (using human red blood cells, HRBCs). The results revealed a clear concentration-dependent trend, where all assessed biological activities increased with higher nanocomposite concentrations.