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No abstract is provided for this article.

No abstract is provided for this article.

Accurate characterization of the underwater stability of superhydrophobic surfaces is crucial for the design of durable anti-fouling materials and advanced microfluidic concepts. Although superhydrophobic breakdown is a major issue that hampers full exploitation of superhydrophobic functional materials, suitable characterization methods are lacking and relatively little is known about the wetting dynamics. In this work we explore a novel method based on attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) for large-area in-situ analysis of wetting states and wetting transitions on nanostructured surfaces. Spontaneous wetting is induced on superhydrophobic silicon nanopillars through in-situ modulation of the liquid composition and surface tension. The high surface sensitivity of ATR-FTIR enables quantitative evaluation of the instantaneous liquid composition and wetted area. Critical transition criteria for superhydrophobic breakdown are assessed using both ATR-FTIR and goniometric measurements. Significant deviations from classical wetting models are revealed, emphasizing the need for more accurate transition criteria and careful experimental validation. Breakdown kinetics near the critical transition are found to be significantly slowed down on nanostructured surfaces, which underlines the necessity for accurate characterization of wetting dynamics at the nanoscale. The proposed ATR-FTIR method can be promising for dynamic studies of wetting transitions on more advanced surfaces, as hierarchical structures or oleophobic designs.

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In the present study, the feasibility of synthesizing chlorinated films by a dielectric barrier discharge at atmospheric pressure is assessed. Two different liquid monomers (hexachlorobuta-1,3-diene C4Cl6 and 1,1,1,2-tetrachloroethane C2H2Cl4) are tested and results show that organic coatings rich in chlorine can be deposited. The correlation and complementarity of water contact angle, X-ray photoelectron spectroscopy, secondary ion mass spectrometry and ellipsometry techniques have provided information to compare the properties of the perchlorinated layers built up from monomers with different Cl/C ratios and hydrogen concentrations. The bond dissociation energies of C–Cl2, C–Cl and C–C/CC/C–H are used to provide an explanation for the differences in films structure recorded by X-ray photoelectron spectroscopy and secondary ion mass spectrometry. Finally, dynamic-secondary ion mass spectrometry complemented by ellipsometry is used to calculate a deposition rate ranging from 40 to 70 nm/min depending on the plasma conditions. These measurements also show a good homogeneity of the film throughout its thickness.

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Cadmium (Cd) has been extensively used as an excellent corrosion protective coating for steel components in aerospace, automotive, electrical and fasteners industries. However, Cd is banned due to its toxic nature and strict environmental regulations. In this study, the electrodeposition mechanism and kinetics, coating morphology and corrosion resistance of alternative, electrodeposited Zinc-Cobalt (Zn-Co) and Zinc-Cobalt-Iron (Zn- Co-Fe) alloys have been investigated. Coatings with relatively high amounts of Co are very difficult to achieve due to anomalism associated with their deposition and are therefore not much reported so far. In this research Zn-Co and Zn-Co-Fe alloys with varying amount of Co (2 to 40 wt-%) and Fe (up to 1 wt-%) are electrodeposited and the effects of variation of process parameter settings (i.e. cathodic polarization, current density, temperature and electrolyte composition) on the electrodeposition mechanism and kinetics are investigated. The microstructure of the alloy coatings changed significantly with the variation in Co content in the deposits. The barrier and sacrificial corrosion protection provided by the coatings were investigated with a variety of electrochemical techniques and industrial accelerated tests. It was found that the sacrificial properties and the protection range decreases with increasing Co content in the alloy. For the highest Co content in the alloy, the coating may become more noble to steel and loses its sacrificial protection. The barrier resistance of the coatings increases with the increase of Co content in the alloy coating. Both Zn-Co and Zn-Co-Fe alloys with high Co content (> 32 wt-% Co) showed excellent barrier properties. An intermediate region of compositions can be distinguished in which the coatings would provide a good combination of sacrificial and barrier resistance properties and also a reasonable protection range. © 2010 by Nova Science Publishers, Inc. All rights reserved.

Green, stable, and wide electrochemical window deep eutectics solvents (DESs) are ideal candidates for electrochemical systems, such as batteries, supercapacitors, catalysis, electrodeposition, and many more. However, since these mixtures are highly dense and composed of only large asymmetric ionic and molecular components, short-range ion-ion, ion-molecule interactions play a dominant role both in the bulk as well as at the interface properties. This results in breakdown of the standard mean-field approximation, which is the basis of dilute solution theory. In addition, due to the hygroscopic nature of DESs, the presence of latent water is unavoidable. Therefore, understanding the DESs-electrode interface (electrical double layer structure, EDLS) together with the role of water at a molecular scale is of great importance for the widespread use of these solvents in electrochemical systems [1-3]. In this presentation, we will first review the benchmark study on conventional dilute solution electrical double layer structure and secondly present our recent findings and theoretical developments on the electrochemical interfacial structure of deep eutectic solvents using a combined experimental and a novel atomistic molecular dynamics approach. In the presentation, we focused on the computational approach. The use of such an atomistic-molecular approach allows investigation of all the possible bulk and interfacial interactions and, consequently, helps to shed light on the nanoscale electrochemical interfacial structure of DESs. Unlike the interfacial structures observed and proposed for other electrolyte-electrode interfaces (compact- diffuse double layer for dilute solution [4]; overscreening or crowding for concentrated solutions [5]), the simulations of DESs-electrode interfacial structure show an unexpected and previously unrecognized phenomenon: the electrochemical interface is composed of a mixed layer structure followed by a mixed charged clustered layer regardless of the surface polarization [1,2]. Some of the findings will be discussed in this presentation. References [1] M. H. Mamme, S. Moors, H. Terryn, J. Deconinck, J. Ustarroz, and F. De Proft, “Atomistic Insight into the Electrical Double Layer of Choline Chloride-Urea Deep Eutectic Solvents: Clustered Interfacial Structuring”, JPCL,9:6296,2018. [2] El A. M. Cherigui, K. Sentosun, M. H. Mamme, M. Lukaczynska, S. Bals, H. Terryn, and J. Ustarroz, “On the Control and Effect of Water Content During the Electrodposition of Ni Nanostructure from Deep Eutectic Solvents”, JPCC, 122: 23129, 2018. [3] M. H. Mamme, S. Moors, El A. M. Cherigui, H. Terryn, J. Deconinck, J. Ustarroz, and F. De Proft, “Water Distribution at the Electrified interface of Deep Eutectics solvent", under review, 2019. [4] G. Jiang, C. Cheng, D. Li, J.Z. Liu, “Molecular dynamics simulations of the electric double layer capacitance of graphene electrodes in mono-valent aqueous electrolytes.” Nano Res. 9, 174−186,2016. [5] M.V. Fedorov, A. A. Kornyshev, “Ionic liquids at electrified interfaces.” Chem. Rev. 114, 2978−3036, 2014.

Coolant corrosion inhibitors are paramount for the durability of automotive heat exchangers. The novel generation of “hybrid coolants” consists of inorganic inhibitors added to an OAT (Organic Additive Technology) backbone. This investigation appraises the corrosion inhibition provided by OAT, phosphate and silicate (separately and combined) on AA6060 exposed to antifreeze coolant at 75°C. The effects of hard water cations and temperature are also discussed. Linear Polarization Resistance provided a time-resolved assessment of inhibition, and potentiodynamic polarisation extrapolated the corrosion behaviour to more severe scenarios. Supported by SEM-EDX analysis, schematic diagrams of the inhibition mechanisms were elaborated for the coolant systems.

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Abstract A modelling approach that combines a previously developed 2D continuum finite element model with machine learning to support the design and evaluation of corrosion-inhibiting coatings. The FEM simulates the leaching of corrosion inhibition pigments from an organic coating and the resulting protection of the metal surface. This is conducted for a system of aluminium alloy 2024-T3 with an active protective coating loaded with lithium carbonate particles. A generated dataset from FEM results was used to train ML models to predict inhibitor concentration and corrosion current density based on geometric and material input parameters. A feature importance analysis was conducted to identify the most influential input variables, providing insight into the factors controlling the achievement of corrosion inhibition. Furthermore, a blind test was performed using five unseen cases that were not involved in the training phase. Finally, the trained models were applied to explore their use in coating design.