关键词: 二氧化钛, 氧化锌, 二氧化钛/氧化锌, 抗菌, 粉体, 复合材料, 制备

Abstract: Due to their high chemical stability and rich and easy raw material availability, oxides as antibacterial materials are receiving increasing attention. In-depth study of the antibacterial properties of oxides and the related influence factors can provide a scientific basis to explore new antibacterial materials. TiO₂/ZnO composite was prepared by sol-gel method, and was compared with TiO₂ and ZnO. The crystal structure, morphology and particle size of these materials were characterized. Using the Escherichia coli ATCC25922 as the tested strain, we investigated the antibacterial activities of these three oxides through bacterial inhibition zone test and bacterial suspension contact test. The effects of titanium-zinc ratio, light and other conditions on the antibacterial properties were also investigated. It was found that the TiO₂ sample was mainly composed of anatase phase and rutile phase, while the ZnO sample was mainly of hexagonal wurtzite phase. And it is mainly the anatase TiO₂ depositing in the pore of hexagonal wurtzite ZnO in TiO₂/ZnO composite. The powder size of the three samples were in a descending order of TiO₂/ZnO, TiO₂ and ZnO. Both bacterial inhibition zone test and bacterial suspension contact test confirmed that the antibacterial performance of the ZnO sample was obviously better than that of the TiO₂. The antibacterial performance of ZnO and TiO₂/ZnO were both good under dark conditions, but became even better under visible light. The comparative analysis demonstrated that the content of ZnO in the TiO₂/ZnO composite played a major role in the antibacterial effect. The calcination temperature during the preparation of TiO₂/ZnO did not show significant effect on its antibacterial performance.

Key words: titanium dioxide (TiO₂), zinc oxide (ZnO), TiO₂/ZnO, antibacterial, powders, composites, preparation