2022/02/11 by Muhammad Waqas Qureshi, Qureshi, Muhammad Waqas, M. A. Ali +9
Engineering · Materials Science · #Aluminum Alloys Composites Properties #Boron and Carbon Nanomaterials Research #FOS: Physical sciences #MXene and MAX Phase Materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2202.05464
openalex publication_date 2022/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
MAX phase family has been extended by the addition of late transition metals at the A-site with the expectation of diverse functional properties, such as magnetism and catalysis. Here, we present our systematic density functional investigation on the phase stability and physical properties of newly synthesized Ti2ZnX (X = C, N) phasesin comparison with conventional Ti2AlX (X = C, N).Due to smaller size of N as compared to C, the unit cell dimensionis reduced when C atoms are replaced by N atoms atthe X-site. The thermodynamic, mechanical and dynamical stabilities are validatedby estimating the formation energies, elastic constants and phonon dispersions, respectively. The elastic properties of Ti2ZnN are nearly isotropic while those of Ti2ZnC are completely anisotropic. To understand the thin-film characteristicsin Ti2ZnX, the surface properties with (001)-terminated slabs are investigated. Both Ti2ZnX bulk and (001)-surfaces exhibit metal-like electronic structure. There is a strong covalent bonding between Ti-X and Ti-Zn atoms.Additional states are generated at the Fermi level (EF) due to the unusual d-pstates hybridization between Ti and Zn atoms.The anisotropy in chemical bonding is confirmed by the cleavage energy difference between Ti-X and Ti-Zn atoms. Here,Ti(X)-001 and Zn-001 terminations are stable surfaces, however, in terms of chemical potentials, Zn-001 termination is the most favorable.