Inexpensive sol-gel synthesis of multiwalled carbon nanotube-TiO₂ hybrids for high performance antibacterial materials

This study reports an inexpensive sol-gel method to synthesize TiO₂-CNT hybrid materials. Synthesized TiO₂-CNT materials show strong antibacterial activity in the absence of light. Cheap TiO₂ source TiOCl₂ is used during synthesis in the absence of high temperatures, high pressures and organic solvents. TiO₂-CNT materials with 0, 2, 5, 10, 15 and 20 wt% of CNT were synthesized and compared for antibacterial activity, surface area, porosity, crystalline structure, chemical state, and HaCaT cell proliferation. The antibacterial strength of hybrid materials increased significantly with the increase in CNT loading amount, and the TiO₂-CNT samples with a CNT loading of 10 wt% or more nearly removed all of the E.coli bacteria. HaCaT cell proliferation studies of synthesized hybrid materials illustrated that prepared TiO₂-CNT systems exhibit minimum cytotoxicity. The characteristics of prepared materials were analyzed by means of XRD, FTIR, Raman spectroscopy, XPS, TEM, and nitrogen gas physisorption studies, compared and discussed. - Highlights: • An inexpensive scheme of preparing TiO₂-CNT hybrids is presented. • Significant increase in the antibacterial properties of TiO₂ in absence of light • Effects of CNT addition on the physicochemical properties of hybrids are studied. • Antibacterial activity increases with increase in CNT content. • Hybrids show no toxicity towards HaCaT skin cell line.