Structural stability, electronic and optical properties of MAX-phase ternary nitrides β-TM4AlN3 (TM = V, Nb, and Ta) using the first-principles explorations

Abstract To explore the scope of application and provide theoretical guidance for the synthesis of MAX-phase β-TM4AlN3 (TM = V, Nb, Ta) ternary nitrides, the first-principles calculations based on density functional theory were performed, and the phase stability, electronic structures and optical properties of these nitrides were predicted. The formation enthalpies of V4AlN3, Nb4AlN3 and Ta4AlN3 were −4.030, −4.065 and −4.048 eV/atom, respectively, indicating that they exhibit structural stability. The results of electronic structures indicated that these nitrides are metallic and V4AlN3 should have a higher electroconductibility than other two nitrides. Based on the predicted optical properties, the applications of β-TM4AlN3 (TM = V, Nb, Ta) ternary nitrides were discussed. Moreover, Ta4AlN3 has the highest optical anisotropy and Nb4AlN3 exhibits the least optical anisotropy.