A comparative DFT exploration on M- and A-site double transition metal MAX phase, Ti3ZnC2

Abstract

The combination of ceramic and metallic properties of the MAX phases makes them attractive for numerous technological applications. The very recent experimental synthesis of the Zn-based MAX phase Ti3ZnC2 is an important addition to the MAX phase family as it further expands the diversity of physical characteristics of this family. Here we have employed density functional theory (DFT) calculations to investigate the structural, electronic, mechanical, lattice dynamic and thermal properties of Ti3ZnC2 for comparison with existing Ti3AC2 phases. Additional transition metal Zn at A-site in newly synthesized Ti3ZnC2 reduces most of the elastic constants and moduli as well as the Debye temperature and thermal conductivity. All the Ti3AC2 phases have the potential to be etched into 2D MXenes with great possibility for Ti3ZnC2. Ti3ZnC2 is highly anisotropic in the Ti3AC2 MAX phase family.

Keywords

• MAX phases
• Density functional theory
• Mechanical properties
• Thermal properties