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The protective action of thin layers of aluminium electroplated on a carbon steel (UNI Fe360B) has been studied. The coatings were obtained via electroreduction, at room temperature, from an ionic liquid constituted by 1-butyl-3-methyl-imidazolium heptachloroaluminate. Coatings of different thickness, ranging from 10 to 40 lm, were obtained. Their morphology and chemical composition were investigated using SEM microscopy coupled with EDX microanalysis and X-ray diffraction. Electrochemical tests (potentiodynamic polarization curves, open-circuit potential and electrochemical impedance spectroscopy) were performed in order to characterise the corrosion resistance of the coating in 3.5% NaCl aqueous solution. Visual investigation of the samples during long term of exposition to neutral salt spray gave an evaluation of their free corrosion properties. It was found that the aluminium layers deposited from ionic liquids significantly protect the substrate from the general corrosion and this action increases with the coating thickness.

The present paper reports the results obtained applying the general purpose software COMSOL Multiphysics Ò to the finite elements simulation of Cyclic Voltammetries (CV's) at microelectrodes arrays (MEA). CV's at inlaid micro disk electrode arrays have been simulated benchmarking our results with those obtained by Compton with the finite difference method. Then the influence of meshing on the quality of the simulated data have been investigated showing that bad meshing may provide shapes with no physical meaning. Simulations have also been performed on recessed micro disk arrays in order to show the effect of the depth of the recess on the voltammetric wave shape. We found that COMSOL Multiphysics Ò provides a flexible and straightforward route to the simulation of electrochemical systems with complex geometry.

Graphical abstractThe “mind-sized” model of overexploitation in fisheries is based on the concept that the fishing industry acts as the “predator” of the resource and that its growth and subsequent decline is directly related to the abundance of the fish stock.

In this paper we report on the electrodeposition of thin aluminium layers on P90 lithium-aluminium alloy at room temperature from a chloroaluminate ionic liquid (1-butyl-3-methyl imidazolium heptachloroaluminate [BMIm]Al 2 Cl 7 ). We found that the treatment of the P90 sample's surface is a key point to obtain good quality coatings. On freshly mechanically polished surfaces, thin (about 24 µm), homogeneous and dense aluminium layers were obtained at 10 µm h − 1 deposition rate. Finally, the corrosion resistance of the uncoated and Al-coated samples was investigated by means of electrochemical techniques such as open-circuit voltage curves, impedance spectroscopy and potentiodynamic polarization in 3.5 wt.% NaCl aqueous solution. We found that the protective aluminium layer significantly reduces the corrosion rates of the P90 Li-Al alloy.

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The AISI 304 and AISI 1018 steels (frequently used in solar collectors' plants) in contact with four different ionic liquids (ILs) suitable as diathermic fluids, were studied. Immersion tests were performed at 220 1C (the working temperature in such plants) for 10 days. The corrosion morphologies of the steels were investigated by scanning electron microscopy coupled with energy dispersive X-ray (EDX) microanalysis and the content of metals in the solution were detected via ICP-OES. The tests showed that the most performing IL is the ethyl-dimethyl-propyl-ammonium-bis(trifluoromethylsulphonyl)imide. The corrosion properties of the two alloys in contact with such IL were investigated by means of Tafel plots and resistance polarization at room temperature in open-to-air vessels. r