International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

One-component CeO2 coatings and bi-component CeO2/ZrO2 multilayer coatings were obtained by a sol gel process. The phase composition, surface morphology and roughness of the samples were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Atomic force microscopy (AFM) and X-ray scanning electron microscopy (XPS). The corrosion resistance and protective ability were characterized by using salty solution of 3.5% NaCl at 25 C. The multilayer configuration of CeO2 and ZrO2 ensure enhanced protection of the steel in comparison to the single CeO2 coatings and uncoated steel. The surface morphology and anticorrosion properties depend significantly on the treatment temperature of both CeO2 underlayer and ZrO2 top layer. At lower treatment temperatures, they are relatively dense and smooth. The corrosion resistance of the multilayers slows down, when ZrO2 coatings were heated above 500oC. This probably is due to the more pronounced crystallization of cubic zirconium dioxide, resulting in deeper boundaries between the individual grains. The protective properties of a CeO2/ZrO2 multilayers could be attributed to the low crystallized structure with very fine crystallites.

Thin films deposited on glass substrates by sol-gel containing ZrO2 show photocatalytic activity, which are compared with TiO2 – which is used as a standard photocatalytic material applied in photovoltaics. By modifying ZrO2, coatings on glass surfaces were obtained, which are characterized by high properties, which are a prerequisite for use in photovoltaics. The coatings are dense and nanocrystal line according to SEM and XRD studies and optically transparent according to UV-VIS-NIR spectra

In this paper, we present the results of atomic force microscopy (AFM) characterizing the surface morphology of nanostructured coatings on photovoltaic glass obtained by the sol-gel method. Two organic titanium precursors were used to prepare the TiO2 deposition solution: Titanium isopropoxide (TTIP) and titanium tetrabutoxide – Ti (OC4H9). The hydrolyzing agent is distilled water and the stabilizer is nitric acid /HNO3/and acetylacetone (AcAc). Many samples were obtained at different ratios of the components involved, rate of application of the solution on the glass substrate, and different curing and holding temperatures. The samples were characterized by AFM analysis.

In this paper we present the results of atomic force microscopy (AFM) characterization of the surface morphology of the nanostructured titanium oxide films featuring with Sm2O3 by the sol-gel method in order to increase the corrosion resistance of stainless steel. Two types of titanium precursors were applied – titanium (IV) isopropoxide Ti[OCH(CH3)2]4 and titanium(IV) butoxide Ti(OCH2CH2CH2CH3)4.

Sol gel method is a simple a low cost technique, which gives possibility to deposit coatings with definitely chemical and phase composition at low temperatures. Here we report an application of sol gel method by dip coating technique to prepare a several type of nanosized coatings: (a) one-component coatings such as TiO2 and Nd doped TiO2 (b) two types of bi-component layers, which contain as underlayer SiO2 and upper layer TiO2 or CeO2. The coatings were characterized by XRD, SEM and AFM analyses. The XRD data revealed anatase phase for TiO2 and Nd doped TiO2 coatings. The presence of cubic CeO2 and SiO2 crystallographic phases were proved in SiO2/CeO2 sample. The morphological investigations of the coatings revealed that they have relatively dense surface. The anticorrosion properties were estimated by exposing the samples to the action of salty solution of 3.5% NaCl and was evaluated by their weight losses. Corrosion attack induces insignificant alteration of the surface morphology of both Nd doped TiO2 samples and multilayer barrier coatings. Pits and other significant visible signs of corrosion are not found according to AFM and SEM analyses. The results proved that the investigated bi-component oxide coatings on the base of titania and ceria deposited on SiO2 exhibit better corrosion resistance than the noncoated steel and one component samples. These type of oxide coatings could be perspective for various applications in industry due to their good anticorrosion properties.

The paper presents the results of the synthesis of the xerogel of vanadium in the interaction of vanadium pentoxide and ammonium. It is shown that as a source of vanadium pentoxide can be used successfully vanadium carbonaceous – siliceous shales. Using obtained vanadate ammonium in receiving technology of vanadium xerogel is more cost effective process than the use for this purpose the chemical reagent. Integrated use of this unique raw material is a critical component of modern waste-free and environmentally friendly technologies to highlight not only the connection of valuable components, but also the raw material for the production of vanadium xerogels.

Synthesized by sol-gel method based on vanadium oxide xerogels with partially ordered highly layered structures already are widely used in various fields of science and technology due to their unique properties. Scope xerogels vanadium: production photocatalysts, composites, membranes and ion exchange materials.