High performance nanostructured coatings using ionic liquids based on choline chloride - NANOCOATIL

Project summary

Recently it has been demonstrated the possibility of forming of ionic liquids from eutectic mixtures of quaternary ammonium salt such as choline chloride (2-hydroxy-ethyl-trimethyl ammonium chloride) with hydrogen bond donor species such as amides, glycols or carboxylic acids .These media, also known as “deep eutectic solvents (DES)” exhibit good air and water stability. They are potentially recyclable, biodegradable and with no harm on human health. Unlike the conventional ionic liquids, the use of DES for a large range of metal surface treatments through electrochemical and electroless processes may be an attractive alternative due to their easy synthesis and manipulation, at a lower cost. They are much safer to use in the workplace than existing aqueous based processes, are stable in use and have a lower environmental impact. The solvents are also environmentally benign and many are biodegradable. Therefore, the sustainability of the new metal finishing ionic liquid electrolytes is greatly superior to both current aqueous systems and alternative ionic liquids. Based on previous excellent experimental results, the present project intends to develop several novel nanostructured coatings, respectively: (i) corrosion resistant Cr/Ni/Co alloys with Mo, V and also metal carbon nanotube (Me-CNT) composites and (ii) ordered nanoporous/nanotubes oxide layers onto valve metal surfaces (e.g., Al, Ti, Nb, Ta) with an enhanced growth rate. Main applications of these coatings are in metal finishing and electronic industries, involving choline chloride based ionic liquids. Through a careful selection of IL based electrolyte composition and operating conditions various nano-morphologies could be obtained, suitable for different final applications. The main advantage of the development and promotion of the use of these new electrochemical media refers not only to the accumulation of new scientific information but also allows the minimization of production costs, of industrial waste quantities, with positive effects on environment and health. The present proposal strongly addresses new processing routes and new solutions to develop nanostructured coatings with tailored properties through optimization either cathodic or anodic reaction. It is expected a significant impact on the development of novel corrosion resistant metallic coatings on one side and of ordered nanoporous anodic oxide layers with a large sectorial use, including metal finishing, electronic, automotive and renewable energy (e.g., PEM fuel cells) industries. Corrosion is a problem that affects in a large extent the manmade structures where metal are extensively used for reinforcement or casing a vast number of products and constructions. Corrosion prevention is a never ending task with large costs for private and national economies. The introduction of new surfaces either with increased corrosion resistance, less costly, produced in more environmentally friendly conditions or absent of more toxic metals will have a big impact in industry and economy of efforts in corrosion hindrance. European industry will benefit from the development of innovative technological applications with less environmental impact that can create novel products with better corrosion resistance, new metal finishing protocols and technology. The European scientific system, in particular the institutions proposing this project will benefit from the work in cutting-edge scientific areas, developing of new methodologies in ionic liquids applications, improving their scientific knowledge to give them a better contribution over industries and to allow the formation of young scientists in a scientific area of great importance.