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This paper addresses the preparation and characterization of protective anticorrosion silane-and polyrhodanine-based bilayer coatings on a tested electrode substrate. Polyrhodanine (pRh) coatings were electrodeposited using the cyclic voltammetry technique on glassy carbon and stainless steel substrates. Isobutyltriethoxysilane (IBTES) films were deposited by the simple dipcoating method on steel substrates and then were stored in air (''aged''). The formed novel bilayer pRh/IBTES coatings were applied on the electrode surface as moderately thin (ca. 6-8 nm thick) layers and exhibited very good adhesion to the steel substrate. The physicochemical properties of pRh, IBTES and bilayer pRh/IBTES coatings were determined with the use of electrochemical, X-ray photoelectron spectroscopy and scanning electron microscopy techniques. The bilayer coatings consisting of a conducting polymer-pRh and silane-IBTES most effectively hinder the access of pitting-causing aggressive anions (chlorides) to the surface of stainless steel and exhibit better barrier properties compared to single-component pRh and IBTES coatings. Graphical AbstractRodanine (1. 2-thioxo-4-thiazolidinone), C 3 H 3 NOS 2

The capacitive and kinetic parameters of hydride electrodes obtained on the basis of single-phase LaNi5-xGex alloys (x = 0.3 and 0.6) were related to their corrosive properties. The content of the article is important from the point of view of the improvement of LaNi5 type materials for hydrogen energy storage used as anodes in NiMH batteries. The presence of large amounts of germanium (10% at.) in the alloy results in much less surface degradation compared to the low-germanium alloy (5% at.), which, on the one hand, leads to an improvement in the resistance of the high-germanium LaNi4.4Ge0.6 alloy to long-term cycling, but on the other hand, contributes to lower hydrogen absorption by this material. The maximum discharge capacity of 293 mAh g−1 was obtained for the low-germanium alloy using a charge/discharge current density of 185 mA g−1. The studied electrode also shows a lower tendency to self-discharge and a clearly higher exchange current density.

Purpose The purpose of this paper is to evaluate and compare the protective, anticorrosion properties of silane- and polyrhodanine-based bilayer coatings pRh/IBTES and IBTES/pRh on an X20Cr13 stainless steel substrate. Design/methodology/approach IBTES/pRh and pRh/IBTES have been coated using the dip-coating method and the cyclic voltammetry technique. The electrochemical measurements have been used to assess the anticorrosion properties of the resulting bilayer coatings. Morphological and chemical characterizations have been performed using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Findings The results clearly show that the combination of both the deposits of polyrhodanine and silane yields a more protective structure that affords better protection against corrosion with time. The best barrier properties are achieved by the substrates coated with polyrhodanine film upon which silane is subsequently adsorbed – the pRh/IBTES bilayer coating. Originality/value The paper reveals that the procedure of modification of silane films with polyrhodanine had a marked effect on the anti-corrosive performance of the obtained two types of bilayers coatings (pRh/IBTES, IBTES/pRh) applied on a stainless steel surface. The coating where polyrhodanine was first electrodeposited on the steel surface and then the silane layer adsorbed (pRh/IBTES) achieved the best protective properties.