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X‐ray photoelectron spectroscopy analysis was applied to investigate the thermal stability under ultra‐high vacuum environment of the surface oxide film formed by electrochemical passivation of a newly designed Cr15Fe10Co5Ni60Mo10 (at.%) multi‐principal element alloy and providing the alloy superior localized corrosion resistance compared to conventional stainless steels and alloys. A spectral decomposition methodology involving the subtraction of Auger peaks overlapping the Fe 2p and Co 2p core level regions was applied for quantification of the oxide film composition and thickness. The results show that, at 100°C, the passive oxide film is mainly dehydrated and dehydroxylated. Obvious loss of Ni hydroxide and conversion of Mo (VI) to Mo (IV) species are observed at 200°C, with further reduction of Mo species to Mo (III) observed at 300°C. In this temperature range, the total cation quantity in the oxide film remains stable despite the compositional alteration. At 400°C, Cr (III) oxide forms at the expense of Fe and Mo oxides, resulting in an oxide film essentially consisting of chromium oxide. At 500°C, Cr (III) oxide is eliminated, making the passive film unstable at this temperature. Possible Cr oxide removal mechanisms are discussed. [ABSTRACT FROM AUTHOR]

Following an industrial process to protect manufactured glass windows against atmospheric corrosion during their storage and transport, this research is focused on the possibility that a surface deposit of a small amount of zinc salts may efficiently reduce the atmospheric alteration kinetics of ancient glasses (soda, potash, and mixed alkali silicates). To this end, the chemical action of zinc salts was investigated by means of aging experiments (with temperature and relative humidity (RH) control) on three glass models, of which compositions are representative of the cultural heritage. When the treatment was performed on pristine glass (about 1 μg/cm2 of deposited Zn2+ ions), treated glass plates developed a significantly thinner hydrated layer than the untreated ones at 80°C or at 40°C (85 RH%). The formation of alkali and Ca‐carbonates salts on the surface was also considerably reduced. The state of the glass surface undergoing the Zn treatment and the temperature of the treatment seem critical regarding the efficacy of the protection. [ABSTRACT FROM AUTHOR]

To investigate the origin of the protection effect of zinc salts against glass atmospheric alteration, the speciation of Zn2+ ions on glass according to the deposit protocol and the Zn2+ surface concentration, and its change over time, was investigated in the light of the respective performances of the treatments. In that respect, a combination of various characterization methods of the glass surface and near‐surface was used before and after aging experiments (temperature, relative humidity (RH) control) of the Zn‐treated glass. Different Zn‐species could be observed on the surface of the treated glass: chemisorbed species, physisorbed species and precipitated hydroxide phases, their respective distribution being highly dependent on the nature of the treatment and on the Zn2+ surface concentration. GI‐XAS (Zn K‐edge) and ToF‐SIMS experiments pointed out the conversion by thermal activation of these surface species into chemisorbed species inserted in the glass network in the near‐surface. The chemisorbed species appear to be the most effective ones for the glass protection, possibly by making the surface less soluble, less hydrophilic and even by acting as a diffusion barrier. [ABSTRACT FROM AUTHOR]

Atomic layer deposited (ALD) 50 nm Al xTa yO z mixture coatings are grown on steel for corrosion protection. In morphological and compositional analyses the coatings are found to be uniform, conformal, well-adhered, and low in defect density. Corrosion protection properties are evaluated with polarization measurements and neutral salt spray (NSS) testing. The sealing properties of the mixtures improve with increasing aluminum oxide content, whereas the protection durability improves with increasing tantalum oxide content. In comparison to single-layer and nano-laminate ALD Al2O3 and Ta2O5 coatings, all mixtures are found to have better protective properties. [ABSTRACT FROM AUTHOR]

The structure of the title hybrid salt, (C5H8NS)[SnCl3], is built up from segregated layers of organic cations and Sn polyhedra. [SnCl3]− groups are linked together by weak Sn⋯Cl interactions to form a one-dimensional polymeric chain of anions. [ABSTRACT FROM AUTHOR]