Realization of diversity in physical properties of Zr2Se(B1‐xSex) MAX phases through DFT approach

Abstract The discovery of a series of MAX phases, Zr 2 Se(B 1‐ x Se x ), with Se at both A‐ and X‐sites, drives a new chemical diversity to the MAX family. Here, we employed the density functional theory (DFT) approach to realize the diversity in physical properties of Zr 2 Se(B 1‐ x Se x ). All compositions of Zr 2 Se(B 1‐ x Se x ) are mechanically stable and the dynamical stability of the end member Zr 2 SeSe is confirmed. The elastic constant C 33 and bulk moduli B show a decrease almost monotonically with Se‐content x while other constants and moduli change irregularly. All elastic constants and moduli except C 12 and C 13 are highest for the end member Zr 2 SeB. Additionally, the Vickers hardness, Debye temperature, minimum thermal conductivity, and lattice thermal conductivity are highest for Zr 2 SeB. The increase of Se‐content x at X‐site reduces most of the properties of Zr 2 Se(B 1‐ x Se x ). The electronic band structures change drastically with increasing Se‐content x . This diversity in electronic band structures is mainly the reason for the diversity in physical properties of Zr 2 Se(B 1‐ x Se x ). All compositions of Zr 2 Se(B 1‐ x Se x ) have the potential to be thermal barrier coating materials, and Zr 2 SeB has the potential to be etched into 2D MXene, Zr 2 B.