Department of Civil and Environmental Engineering, University of Ulsan, Daehakro 93, Namgu, Ulsan 680-749, Republic of Korea.
Department of Civil and Environmental Engineering, University of Ulsan, Daehakro 93, Namgu, Ulsan 680-749, Republic of Korea.
J Colloid Interface Sci. 2014 Aug 15;428:24-31. doi: 10.1016/j.jcis.2014.04.030. Epub 2014 Apr 24.
Ag doped TiO2/glass fibers (Ag-TiO2/GF) were prepared and used for photocatalytic disinfection of Escherichia coli (E. coli) in an indoor air environment. The prepared photocatalysts were characterized using scanning electron microscope (SEM) for morphology, X-ray diffraction (XRD) for microstructure, UV-Visible diffuse reflectance spectra (DRS) for optical properties and X-ray photoelectron spectroscopy (XPS) to determine elemental state. The optimized weight fraction of TiO2 in the TiO2/glass fiber (TiO2/GF) was 3%. The silver content in Ag/TiO2 was altered from 1% to 10% to investigate the optimal ratio of Ag doped on the TiO2/GF for the photocatalytic disinfection of E. coli. Doped Ag enhanced the electron-hole separation as well as charge transfer efficiency between the valance band and the conduction band of TiO2. The generated electron-hole pairs reacted with water and molecular oxygen to form strong oxidative radicals, which participated in the oxidation of organic components of E. coli, resulting in bacterial death. The photocatalytic disinfection activity under visible light increased with the increase in silver content up to 7.5% and then decreased slightly with further increasing Ag content. Among the three humidity conditions used in this study (40±5%, 60±5%, 80±5%), the highest disinfection ratio of E. coli by the photocatalytic system was observed in the intermediate humidity level followed by the high humidity level. Using the 7.5% Ag-TiO2/GF and the intermediate level of humidity (60±5%), the highest disinfection ratio and disinfection capacity of E. coli were 93.53% and 26 (CFU/s cm(2)), respectively.
Ag 掺杂 TiO2/玻璃纤维（Ag-TiO2/GF）被制备并用于室内空气环境中大肠埃希氏菌（E. coli）的光催化消毒。使用扫描电子显微镜（SEM）对形貌、X 射线衍射（XRD）对微观结构、紫外可见漫反射光谱（DRS）对光学性质和 X 射线光电子能谱（XPS）对元素状态进行了表征。TiO2/玻璃纤维（TiO2/GF）中 TiO2 的最佳重量分数为 3%。Ag/TiO2 中的 Ag 含量从 1%变化到 10%，以研究 Ag 掺杂 TiO2/GF 对 E. coli 光催化消毒的最佳比例。掺杂的 Ag 增强了 TiO2 的价带和导带之间的电子空穴分离以及电荷转移效率。生成的电子空穴对与水和分子氧反应，形成强氧化性自由基，参与 E. coli 有机成分的氧化，导致细菌死亡。可见光下的光催化消毒活性随银含量的增加而增加，增加到 7.5%后略有下降，进一步增加 Ag 含量则略有下降。在本研究中使用的三种湿度条件（40±5%、60±5%、80±5%）中，光催化系统对 E. coli 的最高消毒率出现在中等湿度水平，其次是高湿度水平。使用 7.5%Ag-TiO2/GF 和中等湿度（60±5%），E. coli 的最高消毒率和消毒能力分别为 93.53%和 26（CFU/s cm(2)）。
