Prediction of a new Sn-based MAX phases for nuclear industry applications: DFT calculations

Abstract Lately, the MAX phases have been gained an enormous technological attention due to their duel inherent metallic and ceramic properties. Herein, we have investigated by means of the full potential linearized augmented plane wave (FP-LAPW) method for determining the structural, mechanical, electronic and thermodynamic properties of 312 MAX phases M3SnC2 (M = V, and Nb). The intended M3SnC2 compounds generally exist in two possible polymorphs α and β polymorph structures. Further, the formation energies are determined meticulously and revealed that V3SnC2 was more stable thermodynamically than Nb3SnC2 compound. Conversely, Nb3SnC2 exposed a superior mechanical properties over V3SnC2 compound. In addition, the elastic constants of these compounds completely satisfied the criteria of the mechanical stability and showed a ductile nature. The Poisson’s ratio and Cauchy pressure have expressed a positive values which signified the ionic characters for the studied compounds. After that, a metallic behavior was confirmed by the electronic structures analysis. Furthermore, the thermodynamic properties such as heat capacity at constant volume and Debye temperature were investigated at high temperature and pressure. The V3SnC2 compound exhibits the highest value of Debye temperature, while Nb3SnC2 possesses a higher melting temperature. The present meticulous study made these compounds as a potential candidates for radiation-tolerant applications.