В Сколтехе разработали легкий метод получения материалов для ядерной энергетики и литий-ионных аккумуляторов.

The results have been published in the Journal of Alloys and Compounds. High-entropy compounds consist of four or more different main elements, in this case—metals and carbon. In this study, researchers synthesized titanium carbide, zirconium, niobium, hafnium, tantalum (TiZrNbHfTaC₅), as well as carbonitride from these components using a new technology. The authors highlight that this substance is one of the most suitable materials for manufacturing ultra-high-temperature ceramic components due to its excellent mechanical properties and thermal stability. However, the synthesis of carbide is highly labor-intensive: it requires meticulous preparation of raw materials and is conducted at ultra-high temperatures—around 2200-2300°C—for an extended period.

“Multicomponent and high-entropy materials have been studied relatively recently. My colleagues and I modeled various structures of carbonitrides with different concentrations of nitrogen and carbon and examined their thermodynamic stability at varying temperatures. We discovered that a high nitrogen content can lead to significant mechanical stresses in the lattice, negatively affecting the material's stability,” said the head of the research, Professor Alexander Kvashnin from the Skoltech Energy Transition Project Center.

To synthesize the carbide and carbonitride, the research team employed the method of plasma dynamic synthesis. This method utilizes a high-speed plasma jet from an arc discharge as a medium for carrying out high-energy plasma-chemical reactions. The arc discharge and subsequent plasma flow are generated using a coaxial magnetoplasma accelerator.

“This work involves the use of a unique scientific installation—the coaxial magnetoplasma accelerator. During an impulse lasting less than one millisecond, a high-speed plasma jet is formed, achieving the elevated temperatures, pressures, and crystallization rates necessary for producing unique nanomaterials.

Together with colleagues from Skoltech, using computational material design methods, we were able to experimentally combine Ti, Zr, Nb, Hf, Ta, C, and N into a single structure. This method does not require special procedures for preparing raw materials, has low energy consumption, and is versatile, enabling the synthesis of a wide range of material classes: carbides, nitrides, oxides, carbon nanostructures, and composites based on them,” commented the first author of the study, Associate Professor Dmitry Nikitin from TPU.

The application of the plasma dynamic method for synthesizing high-entropy carbides and carbonitrides results in the production of high-quality monophase powders. This method not only effectively yields pure high-entropy carbide TiZrNbHfTaC₅ in a dispersed monocrystalline form but also facilitates the incorporation of nitrogen into the crystal lattice, thereby synthesizing structures similar to carbonitride. By using a carbon-free precursor mixture in a nitrogen atmosphere, materials containing up to eight weight percent of nitrogen can be produced.