双相等离子体Au/TiO2纳米复合材料抗菌研究

Dual-phase Plasmonic Au/TiO2 Nanocomposites with Efficiently Antibacterial Activity

摘要:

具有独特的表面等离子体共振（SPR）的金属纳米晶体是一种良好的宽带隙半导体可见光敏化材料。本研究通过溶剂热和煅烧合成了0.3％摩尔比的金修饰氧化钛（Au/TiO2）纳米复合材料。利用X射线晶体衍射（XRD），X射线光电子能谱（XPS），透射电子显微镜（TEM）和紫外-可见（UV-vis）等方法对合成的Au/TiO2纳米复合材料进行表征。结果表明，由于强的表面等离子体共振效应，Au纳米颗粒可以显著提高TiO2的可见光吸收性能。随着煅烧温度的升高，可见光吸收峰从?550 nm红移到670 nm，这便于更好地利用太阳光谱。Au/TiO2纳米复合材料对大肠杆菌（E. coli）的抗菌活性显示，在450 ℃下煅烧后形成的金修饰的锐钛矿相和金红石相的混晶相，具有最好的光催化抗菌活性。

Abstract:

Metal nanocrystals with unique surface plasmon resonance (SPR) are a good wide bandgap semiconductor visible light sensitized material. In this study, 0.3% mole ratio gold-modified titanium oxide (Au/TiO2) nanocomposite was synthesized by solvothermal and calcination. The as-synthesized Au/TiO2 nanocomposite was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), andultra-violet-visible (UV-vis) analysis. The results showed that the Au nanoparticles could significantly improve the visible light absorption properties of TiO2 at this lower content due to the strong surface plasmon resonance effect. With the increase of the calcinated temperature, the visiblelight absorption peak changed from ~ 550 nm to 670 nm, which is better for usage of the solar spectrum. The antibacterial activityfor Escherichia coli (E. coli) of Au/TiO2 nanocomposite shows that the mixed crystal Au/TiO2 with anatase and rutile phase, calcinated at 450 ℃, have the highest photocatalytic activity.