For the first time, our Group has demonstrated the preparation of different classes of high-entropy materials, including alloys and carbides of four and five equi-atomic components, by electrochemical deoxidation of metal oxide mixtures in molten CaCl2. Varying the experimental conditions, in terms of starting precursor mixture, processing temperature and time, provided different materials of diverse morphologies, ranging from nano-powders to porous or dense 3D objects, as they are in demand for energy, bio and structural applications. The materials prepared were found to be hard and strong, owing to solution strengthening, and showed excellent mechanical and corrosion properties.
Overall, this research has provided a bridge between the concepts of electro-deoxidation in molten salts and the concept of high-entropy materials. The novel findings promise a straightforward, low-energy and cost-affordable electrometallurgical process to produce high-entropy alloys and compounds for advanced applications in large quantities. The presentation highlights results of all these studies.