Studies and researches regarding the obtaining of multifunctional nanocomposites coatings

The paper presents the preparation of ZnO - SiO₂ nanocomposite coatings by successive layers deposition using sol-gel method, dip-coating technique. The influence of the drawing speed and number of layers on the film morphology, optical properties and corrosion resistance were monitored. It has been found that the increase in drawing speed and the number of layers results in an increased film thickness and a modified film morphology by spherical restructuring. The films deposited on a glass substrate have a transparency ranging from 45-90% in the VIS-NIR range depending on the film thickness. In the case of non-transparent substrates, it has been found that these films diminish the reflectivity due to the surface morphology and the presence of ZnO nanoparticles that absorb some of the light radiation. The corrosion test has showed that all of the deposited films provide superior protection to the substrates. (paper)