溶胶凝胶法制备二氧化钛基抗菌薄膜及其性能研究

【作者】 陈小兵；

【导师】 黄慧民； 邓淑华；

【作者基本信息】 广东工业大学 ， 化学工艺， 2004， 硕士

【摘要】 随着社会的进步以及人民生活水平的提高，人们对健康的生存环境日益关注，抗菌防菌意识不断增强。自70年代中期以来，人们对二氧化钛的光催化活性进行了大量的研究，利用二氧化钛来消除与降解污染物成为环境科学领域的一个非常活跃的研究方向，然而，迄今为止，对二氧化钛光催化材料的应用仍然采用TiO₂颗粒的悬浊液，其缺点是溶液中的颗粒难以回收。制备半导体膜的固定化是解决这一问题的有效途径之一，而溶胶凝胶技术可以实现薄膜的固定化。科学家发现二氧化钛光催化材料具有广谱抗菌性，在光照下，对各种常见的致病菌均有一定的抑制与杀灭作用。银离子、铜离子也具备杀菌作用，能杀灭常见细菌，尤其是银离子杀菌力极强，杀菌耐久性良好，用量少，无菌，无刺激，研究表明：以二氧化钛薄膜作银、铜等离子的载体，能使二者抗菌特性互补，可极大提高抗菌性能。 正是在这种背景下，本文回顾了抗菌剂的发展概况，综述了无机抗菌剂在制备方法、抗菌性能等方面的研究进展，详细讨论了纳米二氧化钛薄膜的制备方法及其光催化活性的研究进展，同时对二氧化钛光催化半导体及含银、含铜无机抗菌剂的抗菌性能进行了综合分析。以钛酸丁酯为前驱体，采用溶胶-凝胶方法，对二氧化钛微晶薄膜的制备工艺进行了研究，解决了TiO₂的固定问题，在普通玻璃表面上获得了负载牢固的透明性较好的锐钛矿型纳米TiO₂抗菌薄膜。研究表明：通过改变溶胶中水、溶剂、硝酸等与前驱体的配比，可控制溶胶的水解聚合速度，生成具有良好成膜性能的溶胶，并得出了较理想的配比（摩尔比）及反应条件为：乙醇／钛酸丁酯=45，水／钛酸丁酯=2，硝酸／钛酸丁酯=0.3，乙酰丙酮／钛酸丁酯=0.5，水解反应温度为30℃。基板的提拉速度为10cm／min，退火温度为450℃，退火时间为1小时。改变溶胶中银离子、铜离子含量，制备出多种掺银、掺铜和同时掺银、铜的TiO₂抗菌薄膜。 本论文还对离子掺杂TiO₂薄膜进行了研究，研究了掺杂比对薄膜光催化性能的影响，分别找出Ag⁺／Ti=5％、Cu²⁺／Ti=2％时TiO₂薄膜光催化效果最佳。通过XRD、SEM对制备出的各种TiO₂薄膜的微观性能进行了表征，并讨论了膜厚、退火时间、退火温度、掺杂量对光催化性能的影响。然后通过各种TiO₂薄膜对大肠杆菌的抗菌实验结果还表明：二氧化钛的抗菌机理是光催化抗菌；而离子的抗菌机理是接触性除菌。分别掺入Ag+、cu2+与Tio:在一起，二者有协同效应，可提高抗菌效果。若同时加入Ag十、cu2+则可进一步提高抗菌效果，有关这方面的研究，过去还未见报道。更多还原

【Abstract】 With the progress of our society and the advancement of living standard,people are paying more and more attention to the healthy environment where they live.Much research has been done on the photocatalytic properties of TiO2 since the metaphase of 1970s. Taking advantage of TiO2 to remove and degrade pollutants has become a very active research direction in the field of environment science. However the application of photocatalysis studies still uses slurries of TiO2 particles which are difficult to be recovered. The immobility of semiconductor thin films is one of the effective methods to solve this problem,while sol-gel technology can realize the immobility of thin films. Scientists have found out that TiO2 has broad-spectrum resistance and can suppress or kill common pathogen to some extent by illumination with light. Ag+ ,Cu2+ are capable of killing most common bacteria,especially Ag+has strong effect in killing bacteria and its effect can last for long.The consumption of Ag+ is very small for it to kill bacteria. Ag+ is bioclean and isn’t irritant.Taking TiO2 thin films as the carrier of Ag+ ,Cu2+ et al,as can complement the antibacterial properties and the antibacterial properties can be enhanced greatly.Under such situation ,in this article,we reviewed the development ,preparation method and antibacterial properties of antibacterial agents.The preparation method,photocatalytic activities and antibacterial of nanometric TiO2 thin films were also discussed in detail.Preparation process of nanosized TiO2 membrane was studied,and the fixation of TiO2 was solved and firm transparent anatase TiO2/glass thin films with nano-crystalline have been prepared by the sol-gel processing using tetrabutyl titanate as a precursor in this paper.Hydrolysis and condensation velocity could be controlled and sol with good filming property was prepared by changing the matching of water,catalyzer,precursor and solvent etc in solution.Good matching ratio was gotten after lots of experiments and analysis.nC2H5OH/nTi(OC4H9)4=45(mol ratio),nH2O/nTi(OC4H9)4=2(molratio),nHNO3/nTi(OC4H9)4=0.3(molratio),n(CH3CO)2 CH2/nTi(OC4H9)4=0.5(molratio). Optimal hydrolysis temperature is 30 C, optimal annealing temperature is 450 C,optimal annealing time is 1 hour.Transparent inorganicantibacterial film can be formed on glass plate under the dropping rate 10cm/min,heat treated at 450"C. Ag+-doped thin films, Cu2+-doped thin films,thin films doped with Ag+ and Cu2 are prepared by adjusting the content of Ag+, Cu2+ in the sol.Ion-doped TiO2 thin films were also studied in this paper.The influence of doping ratio on the photocatalytic properties was studied. Ag+/Ti=5%(molratio) and Cu2+/Ti=2%(molratio) have the optimal photocatalytic effect on TiO2 separately.The samples were tested by XRD,SEM methods. And their photocatalytic performance has been tested in terms of film thickness, time duration, annealing temperature,the ratio of dopant.Then the antibacterial capability of the prepared TiO2 thin films was evaluated.According to the experiments to Escherichia coli,metal ions such as Ag+ or Cu2+ can be antibacterial by contact. TiO2 thin film is antibacterial through photocatalysis. And if Ag+ or Cu2+ was doped with TiO2 .cooperation effects which can enhance the antibacterial effect happen. And if Ag+and Cu2+ are doped with TiO2 at the same time,more antibacterial effect can be enhanced.Studies about this field was seldom published in the past.更多还原