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International audienceElectrochemical rest potential and cyclic voltametry were used to investigate the behaviour of the 6% Al magnesium alloy AM60 in various zirconium or titanium fluoride aqueous acid solutions. These solutions have a wide range of aggressiveness with respect to AM60 due largely to fluoride concentration and in some cases to their highly acidic nature. The morphology and composition of the resulting film have been determined by Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray spectroscopy (EDX). The film nucleation is promoted by a pH increase due to water reduction and is thus more likely to occur on the cathodic parts of the surface. Correlatively, film formation on the anodic primary solid solution occurred in only one solution

Highly selective dehydrogenation of formic acid in water was observed at near ambient temperature on a metal/metal oxide catalyst composed of platinum ruthenium and bismuth with a low activation energy of 37.3 kJ mol(-1).

International audienceThe behaviour of the 6% aluminium-magnesium alloy (AM60) surface in zirconium or titanium fluoride aqueous acid solutions was studied. X-ray photoelectron spectroscopy was used to investigate modifications in the surface chemistry with respect to the composition of the surface treatment solution. The surface film is composed of magnesium hydroxide and hydroxyfluoride, zirconium oxide, oxyhydroxide or oxyfluoride, titanium oxide and structural and adsorbed water. Optimal parameters leading to the formation of a zirconium- or titanium-rich film were determined. A mechanism is proposed for the formation of zirconium- or titanium-based films

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