摘要
采用溶胶-凝胶法对TiO2进行Zn、Co单一掺杂及Co-Zn共掺杂改性。以大肠杆菌、金葡萄球菌、白念球菌为实验菌种,研究在可见光照射下各掺杂元素、反应因素对对抗菌活性的影响。运用X射线衍射(XRD)、扫描电子显微镜(SEM)、比表面仪(BET)、傅里叶变换红外光谱(FT-IR)和紫外可见漫反射光谱(UV-Vis-DRS)等测试手段对材料进行表征。实验结果表明,Zn离子掺杂可以引起TiO2能级结构的变化,既可以接受TiO2价带上的激发电子,也可以吸收光子使电子跃迁到TiO2的导带上,另外Zn/TiO2纳米材料中含有27%的ZnTiO3,ZnTiO3具有光催化活性,能够抑制菌种生长;Co/TiO2纳米材料掺杂改性抗菌剂中,Co组分的存在通过抑制TiO2的晶粒长大,使TiO2晶粒尺寸减小,从而增大晶粒的比表面积。Co离子单掺杂在TiO2能隙中引入了Co4f杂质能级,即TiO2的价带与Co的4f电层间发生了迁移,生成捕获能级,降低了禁带宽度,增加了Co/TiO2对可见光的吸收,增进抗菌剂的光催化性能,提高抗菌性;Co-Zn/TiO2纳米材料的抗菌效果最优,Zn、Co共掺杂TiO2促进了Zn、Co离子的溶出。由于Zn、Co离子本身也具有杀菌作用,它们渗透细菌细胞壁并抑制酶活性导致细菌死亡,但是可能由于对微生物攻击的目标不同,当微生物同时接触Zn和Co离子时,细胞膜上的不同位置都受到了攻击,导致更有效的损伤。
Cobalt doped titania (Co-TiO2),zinc doped titania (Zn-TiO2) and Co/Zn co-doped titania (Co/Zn-TiO2) nano-materials were synthesized by a sol-gel method.Using E.coli,S.aureus and C.albicans as target strains,the effects of various doped elements and reaction factors on antibacterial activity under visible light irradiation were studied.Nano-materials were characterized by X-ray diffraction (XRD),scanning electronic microscope (SEM),specific surface area analyzer (BET),UV-vis diffuse reflectance spectra (DRS) and FT-IR analysis.The experimental results show that zinc doping could cause changes in the structure of TiO2,accepting excited electrons on the valence band of TiO2,and absorbing photons to cause electrons to transition to the conduction band of TiO2.In addition,Zn/TiO2 nano-materials contained 27% ZnTiO3,which had photocatalytic activity and could inhibit the growth of strains.The presence of Co component in the Co/TiO2 nanomaterial increased the grain size of the TiO 2 by inhibiting the grain growth of the TiO2,which increased the specific surface area of the crystallite.Co ion introduced the impurity level of Co4f into the TiO2 energy gap,that is,the valence band of TiO2 transferred with the 4f electric layer of Co to generate the capture level,which reduced the band gap width and increased the absorption of visible light by Co/TiO2,thus enhancing the photocatalytic performance of antibacterial agents and improving the antibacterial activity.The antibacterial effect of Co-Zn/TiO2 nanomaterials was the best.Co-doped of Zn and Co with TiO2 promoted the dissolution of Zn and Co ions.As Zn and Co ions themselves also had bactericidal effects,they penetrated into the bacterial cell wall and inhibited the enzyme activity,leading to the death of bacteria.However,due to the different targets of microbial attack,when the microorganisms were exposed to Zn and Co ions at the same time,different positions on the cell membrane were attacked,resulting in more effective damage.
作者
时代
杨合
薛向欣
SHI Dai;YANG He;XUE Xiangxin(Institute of Metallurgical Resources and Environmental Engineering,Northeastern University,Shenyang 110004,China;Faculty of Mechanical Engineering,Shenyang Politechnic College,Shenyang 110004,China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2019年第10期10133-10139,共7页
Journal of Functional Materials
基金
国家自然科学基金重大资助项目(51090384)
