Facile preparation of TiO₂/ZnO composite aerogel with excellent antibacterial activities

TiO₂/ZnO composite aerogel is synthesized using Zn(NO₃)₂·H₂O and titanium butoxide as precursors through sol-gel route combined with C₂H₅OH superfluid drying technique. The effects of the Zn²⁺/Ti⁴⁺ molar ratios and concentration on the antibacterial properties of TiO₂/ZnO composite aerogels are investigated. The results show that the specific surface area is as high as 180 m²/g for the samples with the Zn²⁺/Ti⁴⁺ molar ratios of 1.5. The composite aerogels have the maximum inhibition zone of 23 nm and 19.5 nm for E. coli and S. aureus, and the minimum inhibitory concentration for E. coli and S. aureus of 100 ppm.