Preparation And Properties Of Antibacterial Film On Aluminum Foil

In daily life,some pathogenic bacteria will cause a major blow to human life and have an effect on the economic development of various countries.So the promotion of developing antibacterial materials is of great significance.Metal can be endowed with antibacterial properties through surface treatment processes,which is one of the current research directions of antibacterial materials,and it contains outstanding application values in the fields of public health,household kitchenware,and sterile packaging.In this paper,the aluminum corroded foil is used as the substrate,the methods of sol-gel&spin coating and sol-electrophoresis are used to prepare TiO₂ film and Ag-TiO₂ composite film on the surface of aluminum foil.For the sol-gel&spin-coating method,the effects of aging time,heat treatment temperature,heating rate,Ag content in sol and other process parameters on the film's micro morphology and phase composition is studied.For the sol-electrophoresis method,the effects of the Ag content in sol,deposition voltage and deposition time on the film's microscopic morphology and composition is discussed.At the same time,various testing methods are used to study and analyze the photocatalytic performance,corrosion resistance,hydrophobicity and antibacterial property of the prepared antibacterial film.Research results show that:TiO₂ film and Ag-TiO₂ film can be prepared on the surface of aluminum foil through sol-gel method and multi-step spin coating method.The aging time of the sol have a great impact on the morphology of the film and the test results show that 72h aging is a preferred process parameter.However,microcracks appear in the film during the heat treatment process due to factors such as bending of the aluminum foil.In the electrophoretic deposition process,a uniform TiO₂ film and Ag-TiO₂ film can be formed on the surface of the aluminum foil by adjusting the voltage and the deposition time,and the film appears to be cracked,but the problem of film cracking is improved after adding the stabilizer polyvinyl butyral(PVB)to the electrophoresis solution.Considering the antibacterial properties of the aluminum foil and the production costs,the best formula of the sol-gel&spin coating method is Ag/Ti=10mol%in the sol.And the EDS results show that the Ti element on the surface of the aluminum foil accounts for 9.94%,and the Ag element is about 0.69%.XRD results show that TiO₂ is the phase of anatase,and Ag is a simple phase.The best formula of sol-electrophoresis is Ag/Ti=5mol%in the sol.And the EDS results show that the Ti element on the aluminum foil surface is about 18.59%,and the Ag element is about 1.00%.XRD results show that TiO₂ is also the phase of anatase.In the methyl orange photocatalysis experiment,the antibacterial aluminum foil with Ag-TiO₂film prepared by the spin coating method can achieve 90%decomposition of the 10mg/L methyl orange solution after 2 hours of light in the ultra-clean workbench and it takes 3h for the prepared film to achieve the same effect.The results of electrochemical experiments show that the TiO₂ film layer prepared by spin coating method and electrophoresis method greatly improves the corrosion resistance of the metal substrate in sodium chloride solution,while the Ag-TiO₂ film prepared by spin coating method can improve the corrosion resistance of the metal substrate slightly.On the contrary,the Ag-TiO₂ film layer prepared by electrophoresis method reduces the corrosion resistance of the substrate.The contact angle tests show that the surface of the aluminum foil maintains a hydrophilic state,and the contact angle is between 15°and 30°before and after the surface treatments.However,the contact angle of the droplets on the surface no longer presents a symmetrical shape after the film layer is prepared.The antibacterial tests show that the aluminum foil with Ag-TiO₂ coating achieves 99.9%antibacterial rate for escherichia coli,which generally meets the requirements of antibacterial products.