Preparation And Optical Properties Of ZnO/TiO₂ Multilayer Composite Films

Nanomaterials are known as"the most promising materials of the 21st century".This material is made of particles of extremely small grain size,it can be roughly divided into four categories:nano powder,nanofiber,nano film,nano block and so on.ZnO(Zinc oxide),titanium dioxide(Titanium Dioxide)as a transparent conductive oxide,TiO₂ has become a hot topic in recent years,and the related performance has been discovered by scholars.ZnO,TiO₂ due to its good piezoelectricity,pressure sensitivity,antibacterial properties and excellent optical properties.It is widely used in solar cells,liquid crystal displays,environmental purification,ultraviolet protection and so on.With the progress of science and technology,the corresponding material properties also need to be optimized and improved.Superimposed ZnO on the TiO₂ to form a composite film,the separation of photogenerated electron holes can be promoted by the coupling of the two energy bands,thus improving the photoelectric properties.ZnO,TiO₂ multilayer composite films were prepared by sol-gel method(Sol-Gel).The lattice size,surface morphology,absorbance and optical band gap of the films were characterized by X-ray diffractometer(XRD)and Scanning electron microscope(SEM)and UV-Vis spectrophotometer.The results are as follows:(1)The intrinsic ZnO of zinc acetate(Zn(CH₃COO)₂H₂O)and ethylene glycol methyl ether(CH₃OCH₃CH₂OH)and ethanolamine(C₂H₇NO)were material to produce an intrinsic ZnO.With an optimum concentration of 0.45 mol/L XRD results show that the(002)diffraction peak growth orientation of the film is better.From the SEM characterization,the surface morphology of the film is flat and the crystallinity is high.UV-visible light indicates a66%transmittance in the visible range at a sample concentration of 0.45mol/L.(2)The intrinsic TiO₂,of different concentrations were studied as tincture titanate(Ti(OC₄H₉)₄),acetylacetone(C₅H₈O₂)The optimum TiO₂ corresponding concentration was 0.65mol/L for raw materials.From the XRD characterization method,the characteristic peak of the sample corresponds to the(101)direction.SEM results show that the sample particles are obvious,non-adhesive and the absorbance of the sample is higher by ultraviolet-visible light.(3)After the optimum concentration of the ZnO,TiO₂ is obtained,the coating is carried out on this basis and discussed.The double layer ZnO/TiO₂ composite film with the optimum concentration of 0.45 mol/L/0.55 mol/L has good crystallization quality,strong absorbance and low band gap.