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Abstract: A new electrochemical method using a non-aqueous electrolyte was utilized for deposition of nanocomposite ceria–alumina coatings on stainless steel substrates. The coatings were obtained in a solution of saturated absolute univalent alcohol with different content of AlCl3 ·6H2O and CeCl3 ·7H2O salts. The as-deposited layers were dense and without cracks. The thickness of the coatings was 2–3μm. After annealing SEM examination showed a microstructure formed by small (100–200nm) compacted spherical grains. X-ray photoelectron spectroscopy (XPS) was used to examine the chemical composition and the oxidation state of the as-deposited and annealed coatings depending on the ceria loading. [Copyright &y& Elsevier]

Abstract: The Cu–Co mixed oxide catalysts were prepared on a La2O3/ZrO2/SS support by thermal decomposition of nitrate precursors. The catalyst samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectrum (XPS) and Brunauer–Emmet–Teller (BET) surface area. The XPS data indicated the formation of some amount of CuO together with the Cu–Co spinel after annealing at 550°C. The Cu–Co/ZrO2/SS thin film catalysts were tested for three-way catalytic performance and showed moderate activity. [Copyright &y& Elsevier]

In this paper we report for the first time that lanthana/zirconia films, electrodeposited on a stainless steel substrate, are suitable for supporting a thin-film coating of Cu-Co oxide catalyst. The catalyst is active towards the O2+CO and NO+CO reactions. [Copyright &y& Elsevier]

Abstract: In this study, we prepared thin films by blending ethylene vinyl acetate copolymers (EVA) containing 12–33(wt.%) vinyl acetate (VA) with polyvinyl acetate (PVAc) and high density polyethylene homopolymers. Large area micropatterns having controlled protrusion sizes were obtained by phase-separation especially for the PVAc/EVA-33 blends using dip coating. These surfaces were characterized by XPS and contact angle measurements. A reasonably linear relation was found between the VA content on the surface (wt.%) obtained from XPS analysis and the VA content in bulk especially for PVAc/EVA-33 blend surfaces. PE segments were more enriched on the surface than that of the bulk for pure EVA copolymer surfaces similar to previous reports and VA enrichment was found on the EVA/HDPE blend surfaces due to high molecular weight of HDPE. Water decreased with the increase in the VA content on the blend surface due to the polarity of VA. A good agreement was obtained between and atomic oxygen surface concentration with the increase of VA content. The applicability of Cassie–Baxter equation was tested and found that it gave consistent results with the experimental water contact angles for the case where VA content was lower than 55wt.% in the bulk composition. [Copyright &y& Elsevier]

Abstract: The effect of cerium oxides film, formed electrochemically on OC404 stainless steel (SS), upon the corrosion behavior of steel in 0.1N H2SO4 was investigated. The modification of the steel surface by deposition of cerium oxides films was found to improve the steel corrosion resistance. A linear dependence between the stationary corrosion potential of the cerium oxides/SS system and the cerium concentration in the oxide film was established. The shift of the corrosion potential in the positive direction was found to depend on the proceeding of a depolarizing cathode reaction of CeO2 reduction (instead of the hydrogen depolarizing reaction) occurring on the cathodic zones, formed by this oxide. On the basis of XPS analyses of the samples, subjected to real corrosion under the conditions of self-dissolution, a pronounced drop of the surface concentration of CeO2 was established. This is a proof of the occurrence of an effective cathode process of CeO2 reduction to Ce2O3, which was then dissolved in H2SO4. Data were obtained (XPS) on the composition and structure of the surface film (SEM) after electrodeposition of cerium oxides and after corrosion in the sulfuric acid medium under consideration for time intervals ranging from 50 up to 1000h. The ICP-AES studies acquired data on the quantity of dissolved elements, forming the passive layer. After exposure to the corrosive medium, the deposited layer showed enrichment in oxides of chromium and aluminium. The passive film on stainless steel, modified in this way, proved to be more stable to the effect of aggressive sulfuric acid medium, compared to the case of natural passive film. [Copyright &y& Elsevier]

Abstract: The effect of laser ablation on copper foil irradiated by a short 30ns laser pulse was investigated by X-ray photoelectron spectroscopy. The laser fluence was varied from 8 to 16.5J/cm2 and the velocity of the laser beam from 10 to 100mm/s. This range of laser fluence is characterized by a different intensity of laser ablation. The experiments were done in two kinds of ambient atmosphere: air and argon jet gas. The chemical state and composition of the irradiated copper surface were determined using the modified Auger parameter (α′) and O/Cu intensity ratio. The ablation atmosphere was found to influence the size and chemical state of the copper particles deposited from the vapor plume. During irradiation in air atmosphere the copper nanoparticles react with oxygen and water vapor from the air and are deposited in the form of a CuO and Cu(OH)2 thin film. In argon atmosphere the processed copper surface is oxidized after exposure to air. [Copyright &y& Elsevier]