利用溶胶-凝胶法在纯钛片表面沉积纳米TiO2:C薄膜涂层,采用X射线光电子能谱分析纳米TiO2:C薄膜的化学成分。根据qbt2591-2003国家工业标准测试纳米TiO2:C薄膜对大肠杆菌的抗菌性能,同时通过透射电子显微镜观察细菌被杀灭的超微结构变化过程,分析其抗菌机理。结果表明,在TiO2:C薄膜中C进入锐钛矿型TiO2晶格内并取代Ti或O的位置从而形成O-Ti-C键合,进而抑制TiO2相变。试样对大肠杆菌20 min可见光催化抗菌率均达到90%以上,具有良好的抗菌效果。其杀灭细菌的超微结构变化表明其主要作用于细菌的细胞壁,引起胞壁穿孔,细胞胀大,细胞内容物外溢,直至细菌完全解体。
Undoped and C-doped TiO2 films have been prepared by sol-gel process.The chemical components of the TiO2:C composite thin film were characterized using X-ray Photoelectron Spectroscopy(XPS).The antibacterial efficacy of the TiO2:C composite film was tested by film applicator coating method.Antibacterial mechanism of TiO2:C composite film was discussed by transmission electron microscope(TEM).It has been observed that C dopants retard the transformation from anatase to rutile phase.Namely,C doping effect is attributed to the anatase phase stabilization.More than 90% of bacterium were killed within 20 minutes which confirm fine antibacterial effect of the film.When studying the ultrastructure changes as the antibacterial material of TiO2:C thin film against Escherichia coli,the work indicated that the antibacterial particles of TiO2:C thin film may produce active oxides which contact the Escherichia coli cell and damage even penetrate the cells wall and plasmolemma to enter into the core to make cytoplasm agglomerate and thus cause the cells dead.