Antibacterial performance of TiO₂ ultrafine nanopowder synthesized by a chemical vapor condensation method: Effect of synthesis temperature and precursor vapor concentration

TiO₂ nanoparticles were synthesized using a chemical vapor condensation (CVC) method, and their physicochemical properties were characterized to optimize the synthesis conditions for antibacterial activity. The antibacterial activities of CVC-TiO₂ nanoparticles and commercialized TiO₂ nanoparticles (P25, Deggusa) were investigated according to UV exposure time and amount of photocatalyst. We found that the specific surface area and the crystallinity of CVC-TiO₂ nanoparticles were varied depending on synthesis temperature and precursor vapor concentration. As a result, the CVC-TiO₂ nanoparticles showed a higher specific surface area and better crystallinity than that of P25TiO₂. More importantly, CVC-TiO₂ nanoparticles generated a larger amount of hydroxyl radicals than P25TiO₂. Consequently CVC-TiO₂ nanoparticles were more effective as an antibacterial photocatalyst than P25TiO₂ under irradiation with UV light. Based-on these results, the optimum synthetic conditions of CVC-TiO₂ nanoparticles for bactericidal effect were found.