掺杂TiO_2光催化膜材料的制备及其灭菌机理

PREPARATION OF THE DOPED TiO 2 FILM PHOTOCATALYST AND ITS BACTERICIDAL MECHANISM

采 用ｓｏｌｇｅｌ 技 术制 备了 掺杂 Ｔｉ Ｏ２ 膜， 考察 了制 备条 件对 溶胶 稳定 性的 影响 ，并 从 Ｔｉ Ｏ２光催化 反应的角 度分析 了膜功能 材料的灭 菌机 理． 结果 表明， 溶胶 化过 程中 温度 对掺 杂胶 体 形成速度及 胶体粒 径分布影 响很大， ４ ０ ℃时 制备周 期短， 胶体 稳定． Ｔｉ Ｏ２ 膜 材料 的灭 菌本 质在 于 其光照激活后 产生的 自由基 Ｏ Ｈ·和 Ｏ －２ ·直接 攻击 细 菌的 细胞 ，致 使细 菌蛋 白 质变 异 或脂 类分 解， 从而杀灭细 菌并使之 分解． Ｔｉ Ｏ２ 膜功能 材料 的灭 菌 效果 与 Ｔｉ Ｏ２ 晶相 组成 直 接相 关， 其灭 菌率 随 膜层中锐钛 矿含量 的增加而

The doped TiO 2 film was prepared by sol gel method. The effects of preparation conditions on the sol stability were investigated and the bactericidal mechanism of the film material was analyzed on basis of TiO 2 photocatalyzed reactions. The results showed that both the forming rate and the particle size distribution of the sol were very sensitive to the peptizing temperature. At 40℃ the sol was stable, and making period was short. The bactericidal essence of TiO 2 film was that the free radical OH·and O - 2· produced by irradiation directly attacked the cell of bacteria, and caused the protein denatured or decomposed, leading to the bacteria to be killed and broken down. The efficiency for killing bacteria was correlative with the crystal phase composition of the TiO 2 film, and the efficiency was increased with increasing the anatase content in the film.