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The goal of this stydy was to explore the potential of the enhanced corrosion resistance of Ti(N,O) cathodic arc evaporation-coated 304L stainless steel using oxide nano-layers deposited by atomic layer deposition (ALD). In this study, we deposited Al2O3, ZrO2, and HfO2 nanolayers of two different thicknesses by ALD onto Ti(N,O)-coated 304L stainless steel surfaces. XRD, EDS, SEM, surface profilometry, and voltammetry investigations of the anticorrosion properties of the coated samples are reported. The amorphous oxide nanolayers homogeneously deposited on the sample surfaces exhibited lower roughness after corrosion attack compared to the Ti(N,O)-coated stainless steel. The best corrosion resistance was obtained for the thickest oxide layers. All samples coated with thicker oxide nanolayers augmented the corrosion resistance of the Ti(N,O)-coated stainless steel in a saline, acidic, and oxidising environment (0.9% NaCl + 6% H2O2, pH = 4), which is of interest for building corrosion-resistant housings for advanced oxidation systems such as cavitation and plasma-related electrochemical dielectric barrier discharge for breaking down persistent organic pollutants in water. 

Using microwave irradiation, PtCo alloy nanoparticles were deposited within a few minutes on COOH‐functionalized MWCNT supports. The obtained catalysts were used for selective hydrogenation of cinnamaldehyde, a reaction whose products are widely used in various fields. In the selective cinnamaldehyde hydrogenation to cinnamyl alcohol, microwave‐prepared catalysts (generically, Pt_xCo_y‐MW) outperformed a catalyst prepared by the conventional method (Pt₁Co₂‐con). The highest selective hydrogenation to cinnamyl alcohol, 89%, was obtained using Pt₁Co₂‐MW, while Pt₁Co₂‐con showed a selectivity of 76%. Characterization results confirmed that the microwave prepared samples had a stronger interaction between Pt and Co than that in the Pt₁Co₂‐con sample. The alloyed Co altered the electronic structure of Pt, leading to favorable adsorption of the C=O bond by the lone‐pair electrons of its oxygen atom. Moreover, the Pt₁Co₂‐MW sample showed neglectable change in catalytic performance (e. g., cinnamaldehyde conversion and selective hydrogenation to cinnamyl alcohol) during recycling experiments.