Preparation And Antibacterial Properties Of SiO₂ Films Of Silver Zinc Complex

The microorganism has the strong influence on the lives of mankind, its influence from favorable and harmful two sides. On one hand, people use the avail beneficial ness of the microorganism to make foods etc; on the other hand, people have to face the constantly harass of the microorganism.The spread and propagation of the harmful germ is seriously threat the health of mankind. Aim at the infection of the infectious germ, we should prevent the infection of the infectious germ efficiently, using antibacterial material is most simple and effective method.In this paper, the Ag-SiO₂ composite films and AgZn composite SiO₂ films have been prepared on normal glass by Sol-gel technique with Si(OC₂H₅)₄ as precursors, AgNO₃ as the source of silver element, ethanol as solvent, HNO₃ as catalyst, assemble glycol as the modifier. We prepare Ag-SiO₂ inorganic compound antibacterial material by dipping the normal glass into Ag-SiO₂ sol. The composite films was investigated by using XRD,FTIR,XPS measurements. By analyzing the experiment process and the experiment outcome, we can have some conclusion:(1) The researches indicated: solution consistency, H₂O, catalyze and DCCA are very important factor to films, the films with an ratio of TEOS: ROH: H₂O: DCCA: HNO₃=1: (10-30): (4-10): (＞1.0): (0.03-0.05) were fine.(2) Citric acid as the Ag⁺ complexing agent, Then the Ag-SiO₂ composite films, with different doping concentration of Ag(Ag/Si=0.01～0.1), can be successfully prepared by dip-coating method. The outcome indicated: the Ag-SiO₂ composite films, Silver in the system always exist in multi-forms. The Ag relatively content on the films surface and its value state distribution of silver particles have changed.(3) As the heat temperature increased from 200℃to 500℃, the bacteriostasis circle of the Ag-SiO₂ composite films decreased which is coincide with the Ag relatively content on the films surface and its value state distribution of silver particles.(4) Maintaining the ratioof silver/silicon(Ag/Si=0.1) and the heat temperature 500℃, we can get the AgZn composite SiO₂ films with the different ratio of zinc/silver(Zn/Ag).By analysising the XPS and Ag_3d spectrum, doping Zn²⁺ can increase the relatively content of silver and the ration of Ag⁺ on the surface of films.(5) In the Ag-SiO₂ composite films of Zn²⁺ doping, the ratio of zinc/silver increase from 0 to 1.5, the bacteriostasis circle of films are increased which are coincide with the change of the relatively content of silver and the ration of Ag⁺ on the surface of films. Doping Zn²⁺ can affect the performance of bacteriostasis.